A TS comedy manga series about a boy transformed into a girl by his little sister's strange drugs. Written and illustrated by Nekotoufu.
Initially serialized online and in doujinshi in 2017 (pool #12768), Ichijinsha began publishing the work in print in 2018, and in 2019 it began serialization in the Monthly Comic Rex magazine. Kodansha USA has licensed the English version and is publishing it under the title "ONIMAI: I'm Now Your Sister!". An anime TV series adaptation premiered in January 2023.