Chika-chan to!

Chika, Nao, and Ryou are all friends...with extra, extra benefits. During a threesome, Nao, a loving and mischevious boyfriend with plenty of affection to go around, proposes Chika try out being a bottom. At first, Chika refuses, but after some convincing from Nao, he eventually gives his ass up to Ryou. Once Chika and Ryou start doing it, a whole new door opens to their relationship.

(Source: Fantasista Inc.)

Included one-shot:
Volume 1: Ame no Hi Syndrome

Chika-chan to! was published digitally in English as Sex with Chika! by Fantasista Inc. through futekiya from February 6, 2020 to January 1, 2021.