A flashy play with plain big breasts. Satomi, a new employee, is not good at socializing and is called "plain girl" at work because of her dull and unremarkable appearance. One day, Yoshino, a co-worker, Kokoro peeks at her changing clothes and is surprised by her large breasts, which are hard to imagine from her usual appearance. Later, Yoshino calls her and tells her that he will be holding a "cosplay karaoke contest" at the new employee welcome party, and forces her to change clothes on the spot, which also serves as a costume fitting. Satomi, who cannot refuse, changes her clothes, but Yoshino is excited by her leotard and rapes her, and even takes a picture of her.