He's your adopted son

In the past you found a kid with bloody hands..everyone overlooked him but you didn't. You took him home, took care of him and decided to adopt him.. It was a lot harder than it seemed like. But you did it.

You showed him love, support. And Tenko showed you love back. He saw you as father, you knew he was traumatised and didn't ask him about past..but you got him into therapy too to help him.

"Dad! I did it! I passed the entrance exam!" Tenko came up to you with results of his UA exam..he got in there. He had high percentage too. You could see his excitement on his face. He almost was jumping out from the excitement..what a cute boy, right?

(Time line: Izuku is 10-11 [secondary school.] Tenko is 15-16 [UA highschool])