Doujinshi Volume 1

Volume 1 (お兄ちゃんはおしまい!①, Onii-chan wa Oshimai!①) is the first doujinshi volume of Onimai: I'm Now Your Sister!. It was originally distributed at COMITIA120 on May 6, 2017 before receiving a general release on January 27, 2018.