Mundanefan's manga / #younger seme x older uke(2)

I liked the story, the fact that two guys grew up as twins, even though they looked different but then in middle school their mother tells them that they are step brothers. The younger brother starts distancing himself from the older brother, but at some point he also starts to hang out with bad company and skip classes so the older brother tries to make him not skip class. The older brother finds the younger brother in the abandoned old school building were he is having sex with a girl. He accidentally disturbs them from having sex and the girl runs away, his younger brother catches him and tells him to replace her... Well the younger guy has a crush on him.. yanno... The art was a bit lacking for the younger guy, his hair seemed off sometimes.

A responsible uke who needs to teach the ways of the inn to the seme heir. The heir who is a playboy, wants a treat for learning the ways of the inn. This leads to the uke and seme starting a sexual relationship.