
So why can't menu live with Maya ...financial reasons but he has a job at cram school.

It's in the middle of a chapter later on when Maya first gets kicked out. Megu mentions that they could find a place together and it would be cheaper than Maya getting a place on his own. But Maya tells Megu no, because then it would put a burden on him as he would have to come up with rent and find a way to help his parents out. And his parents are both healthy but older and they are on the poorer side. It also could be considered part of a cultural custom to help the family, especially elderly family members, so that they can retire/take time off.
I don't want the dad to remarry
His co worker she needs to leave him alone. It's so bittersweet this manga.