This is absolutely so hot, mc reincarnates as the villainess as a Futa and basically fucks everyone 😍

Sauce: Otome Game no Akuyaku Reijou ni Tensei Shitara Ura Settei de Futanari deshita
Author: Sella
Pages: 29

Found another really good one a FutaStudentxTeacher, too bad it hasn't been translated yet.

Sauce: Jokyōshi o harama se makuru futanari JK-tachi no ohanashi (535571)
Pages: 53
Author: Gekokujou

Found some of my favorite kinds, a SisterxFutaSister

Name: When my shut-in sister grew a dick (535651)
Pages: 39
Author: Ekogi

This Futa doujin series is literally so good. not only is it so hot, the plot is actually quite interesting too.

Sauce: Otonano Ochimiya (26 Chapters)