Doujinshi Volume 4

Volume 4 (お兄ちゃんはおしまい!④, Onii-chan wa Oshimai!④) is the fourth doujinshi volume of Onimai: I'm Now Your Sister!. It was originally distributed at COMICA123 on February 11, 2018 before receiving a general release on April 10, 2018.

Trivia
第四卷
 * First instance of a 0.5 chapter being released out of order.