Tsutsukakushi Tsukiko

is the female protagonist of the The Hentai Prince and the Stony Cat light novels and related works. She is Tsukushi's younger sister and referred to as younger sister by Youto. Her rival is Azusa Azuki and their tension between each other is intense.
==Appearance==
Tsutsukakushi Tsukiko has a small nose, slender shoulders and arms, a delicate chin, petal-colored lips, and fair skin. Tsukiko's bangs are held back by a pale pink hairpin as well as a bright pink bow on the right side. The rest of her shoulder-length light grayish hair is tied up in a side tail to the left. She has warm grey-blue eyes. Apparently she's very flat-chested and rather short as well, since she was once mistaken as an elementary grade child. She can mostly be seen wearing her school uniform, which consists of: A white buttoned up t-shirt with a yellow ribbon on the collar, two green leaves patterned on the collar, and light pink buttons on the cuffs and on the front of her chest, a red tartan skirt, and black knee-length socks with light brown shoes. Outside of school Tsukiko is usually seen wearing lolita-style clothing. 
==Personality==
Throughout the story, Tsukiko is shown to be shy and insecure at times, yet can be incredibly brave and strong-willed when it comes to the things she truly cares for. Another notable trait is her incredibly large appetite: she is shown to focus solely on eating whenever there is food present, and is able to devour large quantities of food at inhuman speeds.
==Relationships==
===Yokodera Youto===
A bond was formed between Youto and Tsukiko after their chance encounter at the nursery school that Tsukiko volunteered at. The two would regularly hang out, and Youto ends up providing her valuable guidance on getting along with children, something she struggled to do at the time. During this time, Tsukiko always wore a mask, and Youto never once saw her face or learned her name. Tsukiko eventually stopped volunteering there as she started attending the same high school as Youto, and challenged him to find her first. However, due to Youto's sacrifice of his memories during his childhood, he would forget about this promise.
Youto and Tsukiko only meet again when they both find themselves a hill with a cedar tree and a Stony Cat statue, intending to rid themselves of an unwanted trait. Their wishes are granted by the cat god, but with unwanted consequences. An alliance forms between them to take back what they've lost, which leads to them resuming daily contact, though Youto remains unaware that they have met before.
As Youto forms friendships with more girls, Tsukiko would grow possessive and attempt to assert her position as the person that Youto knew for the longest time. Later on, in a time travel back to the past made possible by the Cat God, they learn that ten years ago, the young Youto had sacrificed his memories with Tsukasa to grant them to Tsukushi, hence making him forget anything that can be considered a memory for the rest of his life. Tsukiko was devastated by this revelation, yet she was unable to alter the outcome. The time leap would also prove that Tsukiko is, in fact, not Youto's longest. However, Youto would assert that despite this, Tsukiko remains the most important person to her, and promised to always be by her side.
The revelation in the time leap leads Tsukiko to make an unconscious wish to remember everything in Youto's stead, after which she would begin to keep a series of notes documenting Youto's every action. She initially disguises the notes in a "point system," where for every interaction Youto has with another girl, he must compensate her through acts like holding hands and hugging. She held a particular grudge against Azuki Azusa, who she viewed as a threat to her position as "number one."
During a field trip, she confronts Azusa under the guise of discussing a hypothetical love triangle, asserting that she should recognize her secondary position. However, despite not recognizing her true intents, Azusa counters by questioning the validity of Tsukiko's rankings and emphasizing that love should stem from mutual acceptance rather than possessiveness, suggesting that Tsukiko's feelings for Youto may not even be genuine. Suffering thorough defeat, Tsukiko begins to recognize her own selfishness and falls into a downward spiral, though she eventually manages to confront her feelings and make up with Azusa.
Around this time, Tuskiko begins to notice a tendency in Youto to sacrifice himself for the sake of others, no matter the cost. Tsukiko challenges Youto's idea that he must save everyone or do something extraordinary to have value, assuring him that she would always accept him. However, Youto's nature proves too deep-rooted to be changed. Eventually, when a "curse" tied to the Tsutsukakushi lineage surfaces and causes a sharp decline in Tsukushi's health, Youto sacrifices his remaining lifespan to the Cat God to save Tsukushi's life.
After Youto's death, Tsukiko would fall into despair. However, a mysterious time loop is initiated, where Tsukiko would retain her memories across loops thanks to the notes she kept — her wish to remember everything in Youto's stead was strong enough for the physical notebooks to persist across time loops. She desperately pleads to Youto to not repeat the same tragedy, but this proves fruitless as each loop would end in Youto's same sacrifice. Tsukiko grows disheartened, but Youto eventually realizes his mistake with the help of Emi, and reconciles with her. Combining their efforts, they manage to find the cause of the time loop and break out of it by once again returning to the past, with the intent to rid the lineage of the "curse" from its root.
Despite the challenges, they succeed in finding the root cause of the "curse" — a belief held by Tsukasa in order to cope with her own declining health, which manifested in Tsukushi due to an inadvertent wish made as an expression of love for her mother. They also learn why Youto grew acquainted with the Tsutsukakushi family during his childhood — it was the result of Tsukasa's wish for a family in her most desperate and lonely times, which separated him from his actual family. The second time leap ends with both wishes being cancelled, bringing them to a brand new timeline.
In the new timeline, Youto would once again grow distant from Tsukiko and the rest of his acquaintances. However, during high school, Tsukiko, still retaining all of her memories through the notes, once again finds him at the hill with the cedar tree. She forces Youto to read through all of her notes, helping him rekindle all of his past relationships. For some time, she grows excessively obssessed with the idea of restoring the world to exactly how it used to be, but Youto helps her understand the importance of embracing the present and allowing relationships to naturally form. They eventually make the decision to burn the notes, realizing that the most important memories will always remain in their hearts.
By the end of the light novel, Youto and Tsukiko are in an official relationship and living together.
===Tsutsukakushi Tsukushi===
Partly due to the death of both of their parents, Tsukiko and Tsukushi share an extremely close relationship since their childhood as they had nobody else to rely on. At one point, the two of them have a fight, leading Tsukushi to make a wish to make up with Tsukiko. The Cat God responds to this wish, materializing a piece of wood and chiseling tools. Tsukushi carves the wood into the image of the Cat God as a gift for Tsukiko, giving birth to the Stony Cat shrine that Youto encounters at the start of the story. In their teenage years, Tsukushi's feelings for her sister reaches a point where she wishes to marry her, while Tsukiko, the more grounded of the pair, worries for Tsukushi's future prospects as she struggles greatly with studies.
===Azuki Azusa===
Though Tsukiko respects Azusa as a senpai, she also viewed her as a rival and the biggest threat to her relationship with Youto. As her possessiveness grows, Tsukiko attempts to assert herself as the "number one." During a field trip, she confronts Azusa under the guise of discussing a hypothetical love triangle, asserting that she should recognize her secondary position. However, despite not recognizing her true intents, Azusa counters by questioning the validity of Tsukiko's rankings and emphasizing that love should stem from mutual acceptance rather than possessiveness, suggesting that Tsukiko's feelings for Youto may not even be genuine. Suffering thorough defeat, Tsukiko begins to recognize her own selfishness and falls into a downward spiral, though she eventually manages to confront her feelings and make up with Azusa.
==Quotes==
* "Remember what you said before? That you'd become my brother. Does that still apply?"
* "Worthless? Just, you say? Since I'm just the worthless old me, I considered possibilities like your memories being altered. Those seem to have just been worthless worries on my part."
* "Help... help! There's some weird girl in the kitchen. I was making rice porridge, but she keeps eating it like there's no tomorrow. Who is that girl?"
* "Words... words mean nothing. A number one deserves the privelleges of a number one. There are some things that must be expressed through action, not just words."
* "Then I shall announce my judgement: You are totally, utterly and completely, even at the very last second of the very last scene of the very last episode, a hopeless pervert."
* "I'm not tasty at all."
==Media Appearances==
===Anime===
===Light Novel===
===Manga===
==Trivia==
* Tsukiko mentions that she had the lowest numbers in her class for the body measurements.
* Tsukiko's voice actor, , is the singer of the anime's ending Baby Sweet Berry Love.
* Tsukiko's CV and Azusa's CV are the two members of the duo .
* On the first light novel's cover, her shadow takes the form of a cat. This is likely a reference to how Youto refers to her as a cat, as she is expressionless.
* Tsukiko is extremely weak to alcohol. Getting drunk just by its scent.
* She made an appearance on The Daily Show with Jon Stewart 9 December 2013 who put up fan art of the NROL-39 Octopus attacking her. Stewart would later hypocritically condemn laws allowing erotica of minors on 20 June 2014, even though the previous year he was involved in disseminating it.
* Tsukiko's favorite colour is pink.
* Tsukiko is ticklish on her feet. 
* Tsukiko is into sweet lolita fashion.
* Tsukiko wishes to become an idol.
===Etymology===
* Tsukiko's family name consists of the characters (cylinder, tube) and (hide, conceal).
* Tsukiko's given name consists of the characters (moon) and (child).
==Navigation==