Looking for a yaoi about a light haired guy (uke) living in a cafe of sorts, a past love (seme, dark haired) of his shows up from high school(?) who cruelly dumped him after having sex and (I believe) ruining the experience for him so he never sleeps with anyone again. The seme ends up staying at the cafe upstairs after the owner leaves and the uke takes over. Remember that the uke also gives blowjobs to random guys in bathroom stalls and jerks off. Remember that they go shopping for new stools together (or something for the cafe).

If I'm not mistaken the manga you're looking for is 12-ji Kara Hajimaru

Yes!! That's the one, thank you 🙂 )