Kotori Mizuki ( manga ) Kotori Mizuki ( 観月小鳥 " Mizuki Kotori " ) is a character and one of the main protagonists of the " Yu - Gi - Oh ! ZEXAL " manga . Although not Duel ing , Kotori has a big role in the series , serving as Yuma Tsukumo ' s important friend and main support . Biography . Kotori is part of Yuma ' s circle of friends , together with Tetsuo , Cathy and Takashi . At school , when Yuma kept challenging himself with impossible tasks with his " kattobingu " spirit , Tetsuo usually made fun of him , while Kotori was always worried . She reprimanded Yuma for being so reckless , but at the same time encouraged him , and was always on his side . Kotori once asked why he tried to do those impossible things , and he answers that the important thing is to challenge , and that when he is with the pendant his parents gave him , he felt like he could do anything . One day , Kotori and Yuma found that Tetsuo had been forced to Duel a guy nicknamed Shark , and after being defeated , he took Tetsuo ' s Deck . Yuma confronted him , but Shark took his pendant and broke it . Enraged , Yuma challenged him to a Duel . Shark accepted , and said that they will Duel on Sunday , in the train station . Later , Yuma kept searching for the other half of his broken pendant until late in the night , with Kotori by his side . Tetsuo appeared and told Yuma not to Duel Shark , as he would never be able to win , and that it was a problem of his . Yuma declined , saying that that ' s already a problem of his as well , as Shark broke his most important thing . Tetsuo gave Yuma the other half of the pendant , saying that he found it accidentally . However , it can be clearly seen that Tetsuo was searching for it as well , judging by its hands . On Sunday , Kotori and Tetsuo supported Yuma during his Duel with Shark . During the Duel , as Astral appeared to Yuma , Kotori worried about him talking " to himself " . Yuma asked if she and Tetsuo couldn ' t see Astral , and they confirmed it . Later , when Yuma defeated Shark , Kotori and Tetsuo congratulated him . In the next day , at school , Yuma was greeted by Cathy , Kotori , Takashi and Tetsuo . Takashi said he heard that Yuma won against Shark , surprising him , while Tetsuo said he let it slip . Takashi said he didn ' t know that Yuma was actually a good Duelist and that he must have hidden , undiscovered talent . Cathy grabbed Yuma ' s arm , saying he must have won through his power of " kattobingu " . Kotori asked if Cathy isn ' t getting a little too close to Yuma and Cathy asked why she had a problem with that . Kotori and Cathy began to yell at one another , as Yuma falls over . At that time , Tokonusuke , eavesdropping nearby and watching Yuma , determined that his next target will be Yuma , and he believed something fishy must have happened for Yuma to beat Shark . He soon later runs over to Yuma , asking him for his autograph , and gives him a " Baby Tragon " card in gratitude . The next day at school , Kotori told Yuma that Tokunosuke was looking for him a minute ago to challenge him to a Duel after school . She told him to be careful , as Tetsuo had heard many bad rumors about Tokunosuke . Yuma refused to believe this , saying that Tokunosuke was a good guy . Later , Yuma met him , telling him that he ' d be happy to Duel . He responded that the Duel will be held where everyone can see . Yuma and Tokunosuke then Dueled . However , Tokunosuke used " Baby Tragon " to take control of Yuma ' s " Number s " , and revealed that the paper which Yuma signed was an agreement to bet on their best cards for the Duel . Yuma used " Baby Tragon " together with " Needle Swordsman " and managed to win . After the Duel , Yuma offered Tokunosuke the " Baby Tragon " card back , but Tokunosuke let Yuma keep it . Tokunosuke then became friends with Yuma and the rest of the gang . After a Numbers holder attempts to rob a shopping mall , Kaito Tenjo a Numbers Hunter , defeats him and absorbs his " Number " , alongside with his soul . Akari was investigating about the incident and commented with Yuma about a " Numbers Hunter " . Later , at school , Astral discussed with Yuma about that " Numbers Hunter " , worried about what is his goal and if he would come after Yuma . However , Yuma didn ' t worry about that . As it was raining , everybody was in the class , wanting to go out and Duel . One of Yuma ' s classmates than suggests going to the gymnasium , and all rushed out towards there . In the way , it started raining more , and Kotori was getting behind . Yuma then told her to run , but when she was crossing the street , a truck was passing on it . Yuma immediately ran and pushed her out of the way , but now the truck was going to hit him . Yuma then notices he wasn ' t hit , and Astral finds the time has been stopped . Then , Kaito , the Numbers Hunter , appears . Kaito explains his servant robot , Orbital 7 , has caused the time freeze , and then , forces Yuma to a Duel , betting his " Numbers " and his soul . With no option , Yuma Duels him . However , even with his " kattobingu " spirit , he wasn ' t a challenge to Kaito , who dominated the Duel . When Kaito was about to win , Orbital 7 warns him his brother Haruto is in bad conditions , and Kaito immediately cancels the Duel and goes after him . With that , time goes back to normal , and Yuma falls on his knees , shocked on noticing how weak he is . Upon his loss to Kaito , Yuma ' s spirit is totally broken . Kotori gets upset with that , and tries to do many things to cheer him up . First , she tries to Duel , but she fails at using the D - Pad . Next , she tries to jump over 20 blocks in the P . E . class , but hits her head at them . Later , she leaps form a high height at the pool , but ends up injured . Yuma and the whole gang take her to the hospital . Yuma yells at her saying to stop doing that dangerous things , and she yells back that its because Yuma is becoming a loser , and cries . This makes Yuma awkward , and he says that she is right and that he will " kattobingu " back from that on . Cathy than gets jealous after Kotori hugs Yuma , and start arguing with Kotori . Yuma explains about the " Numbers " , and the gang start discussing about that . They then come up with the idea of creating the Numbers Club in order to help Yuma . The Club then start looking for clues about the " Numbers " , and Tokunosuke finds an information that " Numbers " exist in the Heartland Theme Park . By that way , they take Yuma to the park . However , the owner of the park , Mr . Heartland , hired three Numbers Hunters , who work in the park , collecting " Numbers " secretly disguised as employees . Yuma and his friends than go to the park , and have fun in many attractions . After trying many of them , they go to a roller coaster attraction called " Nature Crooz " , owned by a popular character from the Theme Park , Captain Corn . However , Captain Corn is one of the Numbers Hunters from the park , and as soon as Yuma enters in the roller coaster , he splits the wagons , separating Yuma from his friends , and challenging him to a Duel betting the " Numbers " . While Yuma and Corn Duel , Kotori , Tetsuo , Cathy and Tokunosuke notice Yuma ' s missing , and try to leave to look for him . But Captain Corn traps and almost kills them . However , Cathy ' s agility saved the group , while Yuma managed to defeat Captain Corn . Yuma and his friend then meet , and eat Captain Corn , who exploded into a pile of popcorn due the explosion of Yuma ' s " Hope Buster " . When Astral absorbs Captain Corn ' s " Number " , Mr . Heartland appears and reveals he is hunting the " Numbers " to destroy Astral ' s home , the Astral World , because it is evil , and Astral is the " messenger " . Yuma defends Astral , which makes the others do as well , but Mr . Heartland clicks his fingers , and a kind of door opens in the floor , making them fall in the " Speed Field " , another attraction in the Theme Park . There , they find another Numbers Hunter from the Park , Thunder Spark , who challenges Yuma to a " Speed Duel " in the " Speed Field " . While Yuma and Astral Duel Spark , Kotori and the rest of the gang watch it from a helicopter offered by the attraction . When Yuma fell in the water , both Cathy and Kotori jumped from the helicopter to the water , doing " Catbingu " , in order to save him . However , he soon came back on his own , making the girls ' effort useless . After jumping into the Speed Field ' s river field in order to save Yuma , Kotori and Cathy are soaked . They are inside a dark stone building , and notice a door in the opposite site of the building . It appears to be a dressing room , full of female clothes . Cathy and Kotori then borrow a dry dress for each . Tetsuo comments that the girls kept arguing the whole way to there , and that its odd how they suddenly look like friends , while Takashi complements saying that the situation shows how complicated a girl can be . Cathy and Kotori then ask Yuma if they are cute with that clothes , and start arguing about that . Seeing that the girls have a good relationship , but keep arguing , Astral comments that its seems to be complicated to maintain a friendship . Takashi and Tokunosuke then notice a big door there , which they all pass by , entering a dark room , decorated with lots of creepy dolls , and featuring a big stairway leading to a Doll House . Suddenly , Cologne comes down the stairs , holding a candlestick . She welcomes them to her House of Dolls , and Astral notes she is Princess Cologne , who was known as the mascot of Heartland . They then notice she was also an enemy , and she confirms it , saying that Yuma and Astral won ' t get out of there . But when Cathy replies saying that a short like her cannot intimidate them , Cologne notices Kotori and Cathy are using clothes from hers . The girls try to excuse , but Cologne doesn ' t listen to them , and enraged , throws the candlestick , which surrounds them with flames , and challenges Yuma to a Duel . During the Duel , Cologne reveals about her past . Cologne was once a doll , who was bought by a rich girl . However , that rich girl soon bought a new doll , forgetting about Cologne , and abandoning her . She was then sent to the disposal plant of Heartland . There , Dr . Faker picked her up and gave her a life . And then , crying , yells that she doesn ' t want to be a miserable doll anymore . This feeling strike Yuma and the others , making Yuma hesitate about the Duel . At that time Cathy notes she was the girl who abandoned Cologne . She gets awkward and confused about what to do , but when she decides telling the truth , Kotori says that she was the one who abandoned her , and apologizes . She did this so that Cologne soothed her anger , and that Yuma could concentrate in the Duel , but Cologne knows she is lying , and gets even angrier , throwing oil in the fire surrounding them so that it gets higher , almost hitting them . When Yuma defeats Cologne , the impact of his " Number " throws her to inside the Doll House , which was in fire . At that time , Cathy dove into the flames and tries to save her , saying that she was the one who abandoned Cologne , and had to save her . Cathy ' s noble attitude makes shocked Yuma and Kotori . In her haste , Cathy accidently grabbed one of Cologne ' s dolls instead of Cologne . This time , Yuma decides to go save Cologne , but , who comes out of the Doll House carrying her in his arms is Grandpa Demetto . Cologne ' s soul was supposed to leave her body , but Demetto gave her his own soul , which allowed her to stay alive . While he sends Cologne out of the fire towards Yuma , he is engulfed by the flames together with the field . Cologne mourns the death of Demetto , who she loved . As she had nowhere to go now , Yuma invites her to live with him in his house . Cologne asks him why he is doing that , and he answers saying that everybody that Duels him becomes his friend . Cologne accepts Yuma ' s invitation , becoming friends with him and the rest of the gang . Later , Yuma and the members of the Numbers Club gather in Cathy ' s house . Everyone get impressed at her mansion . Astral comments that it is much better than Yuma ' s house . Cathy then tells Yuma that if he marries her , all that would be his , and Kotori doesn ' t believe she said that and yells at her . Cathy then presses a cat paw - like button , which opens a door leading to a big room , with many researchers and big computers . Cathy explains that as an apology for the trouble she caused , the Numbers Club ' s headquarters would be established there , where they can look up mysterious phenomenons happening throughout the world , and therefore , locate the " Numbers " . While the guys get amazed on the technology and say how Cathy is really put into it , Kotori sarcastically says Cathy is letting her money do the talking , while she replies saying asking if Kotori could do that . The Numbers Club then start helping Yuma , wearing new super hero - like outfits . After Kaito Tenjo ' s Duel with Hishakaku and Yuma Tsukumo and Orbital 7 saving Kaito Tenjo from a fall that would have killed him , Kotori visited Yuma and Cologne at Yuma Tsukumo ' s house and they both hearing screaming in Yuma ' s room , so they checked it out and they saw Kaito knocked out by Cologne . After Kaito woke up , Kaito was wondering why he was saved by Yuma Tsukumo and Orbital 7 , but he was interrupted when he saw Astral in the room , so he turned on his Duel Gazer tattoo and tried to Duel , but found out that Yuma hid it away , so he could rest . Kaito also looks at Kotori thinking that she did while she was shocked and nervous . They went to the kitchen , so Kaito could eat and have the energy to find Haruto , but they failed twice when they were trying to cook eggs . Fortunately , Akari and Haru arrived with food and everyone started eating . Akari asked Kaito how he knows Yuma , so Kaito told her that he was a natural born Duelist , but was interrupted when Yuma accidentally spit out his food and Yuma changed it to Karaoke Duet and they sang a little as an example . A hour later , while Kaito and Yuma were talking , Akari told Yuma to take Kotori home and Yuma got dressed and they went Kotori ' s house . Once Yuma dropped off Kotori five feet from her house , Shadow knocked out and kidnapped Kotori to lure Kaito , Ryoga and Yuma to a trap . Once a ransom note on a blank card was retrieved to Kaito and Yuma at Yuma ' s house , Kaito left to battle Shadow to save Kotori . Once Yuma arrived at the spot where Shadow and Kaito were Dueling , Kotori woke up and Yuma was holding her steadily to get up from the ground . The next day , Yuma was in a hurry after school to find Kaito and Shark before something bad happened and Kotori was trying to catch up to Yuma . Before she could , time stopped and as Kotori didn ' t possess a " Number " she remained stopped in the edge of the sidewalk while Yuma was watching Shark and Kaito Duel and later while Yuma Dueling Shadow . A few weeks later , the whole gang went to the hospital to see Tetsuo getting out of the hospital feeling better after his injuries from his Duel . Once Tetsuo finds out that the Numbers ' Club hasn ' t disbanded , but they were doing their own thing during the time he was in the hospital . Yuma also told Tetsuo that he wants to partner up with Shark and Kaito to beat Kyoji Yagumo to end the Numbers War . Tokunosuke showed Kotori and the others that he bought tickets to the opening of the new Heartland Tower in Heartland and everyone was shocked and happy . Everyone said yeah together with their hands up . The next day , Kotori and the others along with Cologne arrived at the opening of the new Heartland Tower , so they hurried up as soon as they saw the line build up . Kotori and the others were wondering where Yuma went and Kotori and the others were shocked when they saw him on the field about to Duel Kaito . After finding out that Yuma Tsukumo was Dueling Kaito Tenjo , Yuma asks Kotori and the others to find Haruto while he distracts Kaito in a Duel . After Kotori and the others found Cologne and Luna while they were looking for Haruto , Luna explains what is going on with the Duel . Tetuso sends Kotori , Cathy , Cologne , and Takashi to find Haruto while He , Luna , and Tokunosuke look for Dr . Faker and stop the device . Kotori and the others travelled through the Disposal Facility to find Haruto , but Cologne told them that it was a shortcut to the real location of Haruto ’ s room . When Kotori and the others got to the top of Heartland Tower , they were shocked to see that the tower was torn apart after Kyoji had destroyed it . Out of nowhere , Kotori and the others saw that something flying toward them and also crashing . Kotori and the others realized that it was Orbital 7 , who crashed in the middle of the four . Kotori begged Orbital 7 for help to find Haruto and that he is being held hostage by Kyoji and Orbital 7 agreed to help find Haruto . When Kotori and the others arrived at a location where Orbital 7 used a computer to find Haruto , the robot found Haruto in the device where the new Duel stadium was located . Tetsuo had Orbital 7 fly Kotori and Luna to the device . Kotori and Luna went through the entrance of the device where Haruto was strapped to be " kept alive " , but actually being used to activate the device to gather the number cards ’ energy to activate the device . Kotori told Yuma to stop the Duel after they found Haruto in the device , but Kyoji had told Kaito that if he stopped the Duel , that Haruto will die . Orbital 7 tried his best to break the cross monument to get Haruto out of there , but he kept failing since the monument was strong enough to survive Orbital ’ s hits . Kotori screamed at Kaito in order to remind him that he is a good guy after he saved her previously . Kotori got worried for Haruto , but the others showed up and helped break the cross monument in half and Orbital substituted for Haruto ' s life - support system . Kotori was worried when the device didn ’ t stop after they released Haruto . Although Yuma told Kaito that Kotori and the others saved Haruto , Kaito was possessed by his " " , forcing Yuma to win to release Kaito from the control of the " Number " . Kotori and the others are sucked into the vortex and protected from debris by Luna ' s pendant before Yuma Tsukumo , Kaito Tenjo , and Ryoga Kamishiro ( manga ) Duel Kyoji Yagumo in the Otherworld Ocean . Kotori cheers Yuma on as the three duel Yagumo . Kotori realized that Yuma had convinced the others to join him in the Duel against Yagumo . Kotori worried for Yuma and the others as the Duel continued . She was pleased to see that if Yuma ' s attack went through they would win the Duel , but Yagumo managed to hang on with 100 LP . E ' Rah appears and took over the Duel for Yagumo , overpowering them with " E ' Rah Monster s " and launching a direct attack at Yuma , causing Kotori to scream Yuma ' s name . She was horrified when Shark took the attack himself and was killed as a result . Kotori and Tokunosuke were pleased when Kaito managed to drive E ' Rah back with a loop combo , but E ' Rah managed to survive and Summoned " Anti - Hope , God of Despair " , defeating and killing Kaito as well . E ' Rah then offered Yuma and Astral the chance to surrender , and in recognition of her tenacity she would make the souls of Yuma and his friends part of her new world , claiming that it was the only way for them to survive , much to Kotori ' s shock . Kotori led her friends in denying that they wanted to be part of a world like E ' Rah ' s and they encouraged Yuma and Astral to win . She was pleased when Yuma revived Shark and Kaito ' s new " Numbers " ; " " and " " , but E ' Rah blocked most of their efforts to defeat her until Yuma and Astral united using ZEXAL , Summoning " " and transforming into the monster to defeat E ' Rah . After the Duel , Astral returned most of Yuma ' s friends to Earth with the exception of Kotori and reclaimed all of the " Numbers " except " Utopia " , which Yuma refused to give to Astral to prevent him from sacrificing himself to seal E ' Rah permanently . Yuma asked Kotori to stay with him as he ha from the beginning . During the Duel , Shark , Kaito and Yagumo explained the flow of the turns to Kotori , and Kotori eventually realized that Yuma was deliberately recreating parts of his prior Duels with Astral . Although Yuma was able to win , Astral used the effect of his " " to take " Utopia " from Yuma , and the two bid a sad farewell . Astral sent Kotori and the others back to Earth before turning to stone . Kotori resumed her normal life at Heartland Academy .