(2018-01-31 23:03:46 UTC) bocchi>Reminder that the original is a gender-bender loli-rape doujin
(2018-02-01 05:14:19 UTC) BCS>"You are searching for: "nekotoufu" and there was 0 results found."
(2018-02-02 03:31:31 UTC) davremedy>GIVE ME THE LINK!
It's not the same artist, but I remember that there was a doujinshi made by "yukino minato" (not "nekotoufu") called "Tsuitenai Shoujo" that is a "gender-bender loli-rape doujin" with a pretty similar starting plot minus the little sister.
The art isn't the same (since it's not the same artist), but the main characters more or less look alike if you look at them from a distance.
And since "nekotoufu" never did any hentai (to my knowledge), my theory is that 'bocchi' probably mistook it for that one.
Warning link NSFW: https://hentai2read.com/tsuitenai_shoujo/
But who knows, maybe "nekotoufu" read that doujinshi and got inspired by that to make this manga. (since "Tsuitenai Shoujo" was released in 2016 and "Onii-chan wa Oshimai" in 2017)