fujomom's manga / #Rich seme(2)

I've read all of this on Lezhin. The main character is pretty immature but for some reason I'm intrigued by this couple. MC gradually gets involved with a man who he thinks is his best friend's lover (she gets involved with older men that like to take care of her), but feels guilty about it. But drama is imminent because he doesn't know the truth of who his new doctor-lover is, then his friend asks him out, and then there's the mysterious past lover of the doctor that's obviously going to make another appearance.

Salaryman Suzuki gets transferred to the country but get frustrated by how the coworkers treat him and their work. He befriends a delivery guy and goes out drinking with him. The delivery guy is actually well-off and asks Suzuki to be his sugar baby