En inherited One For All from Daigoro Banjo, the fifth user, after Daigoro was crushed under rubble. Daigoro managed to extend his hand so En could consume his blood and claim the quirk.
All For One came after him trying to steal One For All, but En held onto it. He eventually met Nana Shimura, and the two clearly had some kind of connection—fans often speculate about the nature of their relationship based on what happens next. When All For One fatally wounded En in combat, his final act was giving Nana a strand of his hair so she could become the seventh user of One For All.
Content compiled by AnimeList.moe from publicly available sources.
