Emi Sakura
On March 22, 2011, Tsukushi entered a tournament to crown the first ever Internet Wrestling 19 Champion; a title contested for exclusively on Ice Ribbon's Ustream program "19 O'Clock Girls ProWrestling". After defeating Mochi Miyagi in her opening match, Tsukushi advanced to the finals, where she managed to score an upset win over the reigning ICE×60, International Ribbon Tag Team and Triangle Ribbon Champion Tsukasa Fujimoto, winning her first title and becoming the inaugural IW19 Champion. On March 31, Tsukushi made her debut for Smash at "Smash.15", where she teamed with Hikari Minami and Riho to defeat Emi Sakura, Makoto and Mochi Miyagi in a six-woman tag team match. On April 10, Tsukushi defended the IW19 Championship for the first time in a special episode of "19 O'Clock Girls ProWrestling", which aired live from the Kashimagakuen High School in Tsukushi's home prefecture of Ibaraki. The title defense against Emi Sakura ended in a nineteen-minute time limit draw, which meant that Tsukushi retained her title. Five days later, Tsukushi successfully defended the title against Makoto at an Ice Ribbon and Osaka Pro Wrestling co-promoted episode of "19 O'Clock Girls ProWrestling". The following day, Tsukushi and Riho unsuccessfully challenged Emi Sakura and Ray for the International Ribbon Tag Team Championship. Also in April, Hikari Minami and Riho began producing their own professional wrestling events under the banner of "Teens", which also became the name of the informal stable, which in addition to the two also included Tsukushi, Dorami Nagano and Kurumi. On April 24, Tsukushi was defeated by Riho in the main event of "Teens.1". As a result of pinning Tsukasa Fujimoto in the IW19 Championship tournament final, Fujimoto agreed to defend the ICE×60 Championship against Tsukushi. The title match took place on May 5 in the main event of "Golden Ribbon" at Korakuen Hall, where Fujimoto retained her title. On May 13, Tsukushi made her third defense of the IW19 Championship, defeating Chii Tomiya. On May 27, she lost the title to Hikari Minami in her fourth defense, ending her reign at 66 days.