In the heart of a bustling anime convention, two young cosplayers, Komi and her friend Mikuni, sneak into an adult-themed panel, curious about the taboo world of hentai. As they watch animated characters engage in explicit acts, they blush and squirm, feeling a strange mix of excitement and shame. Their eyes widen as they see a scenario that echoes their own forbidden feelings - a stepsister and brother unable to resist their mutual attraction. As the anime reaches its climax, so do Komi and Mikuni, their bodies tingling with newfound desires they can't yet name.