Dadzawa - Aizawa as a papa
20 parts Complete Mature[discontinued] When Aizawa and Hizashi were younger, they had helped their friend out by donating their s***m so she could get pregnant, the two had also decided that they wanted to see their child as often as they could but when the two were told that the child was dead, they gave up on their dreams to help her raise their child.
Since then, years have gone by but how will Aizawa and Mic react when they found out that not only was their child alive but that it didn't contain only one of the two's DNA but that the child had three sets of DNA meaning they had TWO fathers and a mother who shot herself a year before.
Read the story, it makes more sense in chapter 7 and 8, btw, they had adopted Shinsou and Eri at an earlier date.