Smile At You Yuuki Yuuna wa yuusha de aru : Season 1 Episode 12

Yuna is forced to fight against Mimori, who can't bear to lose her memories of everyone like she did with Sonoko, or be forgotten about herself. However, Yuna states her determined feelings to never forget about Mimori and manages to stop her. With the Vertex's final attack headed for Shinju, all of the girls, despite the afflictions caused by their Mankai forms, band together to block the attack, with Yuna delivering the final blow just in time, after which their fairies disappear, ending their role as heroes.