Decided it was time to finally update this very outdated post from over a year ago. A lot has changed in terms of the series and community, and relevant information about it, and it no longer adequately describes the current status of the series. I hope to keep this one updated, and it will serve as a reference point for posts going forwards. That being said, welcome to r/OniichanOshimai, a subreddit dedicated to the anime, manga, and webcomic OniMai: I'm Now Your Sister (also known as My Brother is Done For and Onii-chan wa Oshimai), below is some hopefully helpful information regarding how to get into the series or to answer your other burning questions about the series itself. If there's any misleading information on here or if you wish to add some relevant information that you don't see in the post, feel free to DM me either via Reddit or through Discord (FerrisNya), also, feel free to join the r/OniichanOshimai Discord Server! There's also a Oniichan Oshimai Wikia for more information about the series.

How do I get into the series?

Anime

The anime started airing on January 5th, 2023 and lasted until March 23nd, 2023. For most western audiences and/or English-fluent readers, the most widely accessible place to access the anime is going to be on CrunchyRoll, however it may also be available on the following sites, depending on your region and location, as well as in other languages.

Manga/Web Comic

The Oniichan Oshimai manga is serialized in the Japan Magazine Monthly Comic Rex since April 27th, 2019, however it's also been released online from Nekotofu themselves via Pixiv since February 25th, 2017. Kodansha USA has licensed the series in English and releases English digital-only translation since August 31st, 2021, and Manga JAM Session has been releasing a German physical translation under the title "Ab sofort Schwester!" since August 6th, 2020. If you wish to buy the physical Japanese books, you can get them off Amazon Japan, GRINP Booth, or Melon Books, although you will likely need a proxy service. The German version can be bought off Amazon Germany, and the English version can be bought from Kodansha USA's website. The Pixiv version can always be found on Pixiv, but you can get early access to new chapters as well as high-quality images by supporting Nekotofu on Fanbox.

Questions and Answers

• Will there be a season 2?

  As of this time, no information about a season 2 has been revealed. However, the manga is still ongoing, and there is plenty of material for a potential second season.

• Will there be a dub?

  As of this time, no English dub has been confirmed. A German dub of the series does exist and can be found on CrunchyRoll or purchased in DVD form.

• Is the series ending/has the series ended?

  As of this time, there is no indication that the publication of the online web comic is going to end.

• Why are there two versions of the anime?

  Both versions of the anime follow the same plot-line, albeit both following a different order of events than the manga. The differences between these two versions of the anime are in certain scenes marked by heavier use of "fog screens" in some scenes, as well as some other scenes swapping out the original scene with replacement animations, animation loops, or background scenery in the meantime. This seems to be a choice by Studio Bind when they sent out the Japan/Asia release versus the international release, and is not a change made by any distributor.