Responses
https://www.mangago.zone/read-manga/yatara_yarashii_fukami_kun/
This one fits your description I think
Not a play boy but they are only fucking because of contract https://www.mangago.zone/read-manga/define_the_relationship/
Any Manga where the ML is a play boy and somehow ends up sleeping with the MC and over time falls for MC, only to find out MC only considered them an f buddy?