Mio Shirai
On October 27, Ohka represented Wave in Sendai Girls' Pro Wrestling's Joshi Puroresu Dantai Taikou Flash Tournament, a single-elimination tournament, where different "joshi" promotions battled each other. Team Wave, which also included Gami, Moeka Haruhi, Shuu Shibutani and Toshie Uematsu, was eliminated in their first round match by Team JWP of Command Bolshoi, Hanako Nakamori, Kaori Yoneyama, Kayoko Haruyama and Leon. On April 30, 2012, Ohka entered the 2012 Catch the Wave, wrestling in the Black Dahlia round-robin block. After a loss to Cherry, wins over Hanako Nakamori, and Misaki Ohata, and a draw against Tsukasa Fujimoto, Ohka finished tied at the top of the block. On July 1, Ohka defeated Fujimoto in a tiebreaker match to advance to the semifinals of the tournament. On July 16, Ohka was eliminated from the tournament in the semifinals by Ayumi Kurihara, who went on to win the entire tournament. On July 27, Black Dahlia and rival group White Tails wrestled to a draw in a five-on-five gauntlet match, which ended with Ohka wrestling Mika Iida to a ten-minute time limit draw. Following the match, Black Dahlia leader Misaki Ohata blamed the result on Ohka, noting that she, as well as Ayako Hamada, Bambi and Cherry, the other members of the stable in the match, were all in their thirties. Ohata then recruited the 24-year-old Mio Shirai to the stable to bring down the average age of the group. The draw between Black Dahlia and White Tails led to the two groups agreeing that the stable, which would manage to draw fewer people to their self-producen Wave event, which would take place August 7 and 8, would disband. The Black Dahlia event was headlined by an eight-woman tag team match between the stable's two generations. In the match, Ohka, Ayako Hamada, Bambi and Cherry were defeated by Ohata, Apple Miyuki, Hanako Nakamori and Mio Shirai, with Ohata pinning Ohka for the win after hitting her with the stable's signature whip. White Tails ended up winning the battle for attendance 201-191, forcing Black Dahlia to disband.