From Renta!

Kaoru is a businessman... and a rookie manga artist... and an "innocent"... who has never had a girlfriend. His manga plotlines suffer from his inexperience in love, and now his editor's put his job on the line. Desperate to understand women, Kaoru drunkenly purchases a bra online. When that still doesn't help, he goes out after work to drink away his sorrow and is approached by an incredibly handsome man. Happy to have some company, Kaoru drinks until he passes out... The next morning, he wakes up in a hotel room in bed with the man from the night before and finds the guy took photos of Kaoru wearing the bra! And now Kaoru's getting blackmailed into doing all sorts of things...!