Neconeco Keiyaku

"Strip if you don't want this to be spread around."

Komano is secretly interested in Konemori, an older classmate who is repeating the year. While he tells himself that he isn't in love, he finds himself exploding from anger after seeing Konemori in a compromising situation with Kurokawa, his friend since middle school. Komano then threatens to expose Konemori and forces him into becoming his sex friend. They continue this strictly physical relationship until one day, Konemori rejects a kiss with an almost crying expression after which he suddenly turns into a cat??

(Source: Libre, translated)