-don't sure is it manwha or webtoon or manga
-sure that it's full color
-MC pick up USB that FMC drop from bus-stop
-MC open that USB and It's BETA test MMO
-if my memory isn't wrong MC character have sex with FMC character in game for power up or something

I just read only first chapter -_-" If anyone remember or know this webtoon/manga/manwha name please do tell
Thank You.

Took me a while to find this one but I finally remembered it had "lust" in the title so here you go:
Log in to Lust-a-land

Thank you very much, it's what I looking for.