Collected Works Volume 1

Volume 1 (お兄ちゃんはおしまい!①②③, Onii-chan wa Oshimai!①②③) is the first collected works volume of Onimai: I'm Now Your Sister!. It is a compilation of Volume 1, Volume 2, and Volume 3 of the doujinshi with added bonus material. It was originally distributed at COMIC1★13 on April 30, 2018 before receiving a general release on March 7, 2021.

Bonus Material

 * Character Profiles: Mahiro Oyama, Mihari Oyama, Kaede Hozuki
 * Oyama Household Floor Plan
 * Afterword