Omae… Onna Datta no ka!? Bishoujo ni Seichoushita Osananajimi to Saikai Shite Icharabu Suru Anthology Comic

"You're so cute now… it's unfair!" That boy you used to play with when you were little...... is not a boy, but a girl! An unexpected reunion with a childhood friend, who has grown up to be a different person than what you expected. She has become a woman in many ways, and it's hard to look her in the eye......... and sometimes they even get a little naughty! This is an comic anthology featuring such unexpected and surpising situations! (Source: Kadokawa, translated)