Not really sure but is it this one http://www.mangago.zone/read-manga/whose_baby_is_it/
By any chance do you remember the plot?
Can remember the plot but m.dure the mc has black hair and the baby on his back has blond or white hair and if am not wrong the mc wears a jacket
The genre? BL or shojo or just slice of life?
Hmmm not sure but kinda remind me about this http://www.mangago.zone/read-manga/monster_child/
Am looking for the title of the manga where the mc has a baby on his back and he kind has short hair guys pls help me find the manga it's been a while I wanted to read that for a long time