Manga Hunt (pt 2)

This is the second manga in my hunt for many more, I hope you guys can assist me once again! (๑•ㅂ•)و✧
It's a yaoi manga that has this plot (I think);
There are two guys, one is in high school and the other works- there's a decent age gap. The student falls in love with one of his classmates who later takes him to a small building where more people are. There's a fight...? Or something? I don't really remember, but the older guy saves him and takes him home. As far as I remember, the two lived with each other the whole time and were step-son and step-father?
Thank you so much, any help is appreciated!