Should be OP (obviously) have a dark past secret identity(not important) lazy or drunk all the time if possible childcare
Main Character Hides His Strength I first wanted to say no childcare, but there actually is, if you include a sentient book
https://www.novelupdates.com/series/isekai-yururi-kikou-raising-children-while-being-an-adventurer/ maybe
The Returner really dark past and really lazy has lost most of his power in the beginning, but is still OP
That's why I said maybe. There are not many novels that have mc babysitting, because most novels are made for teens, and created by teens who have no experience in babysitting.