A "What if Izuku's father, Hisashi Midoriya, is All for One?" theory fanfic. How would everyone react, especially Izuku himself? Takes place in their 1st year overlooking Season 3/manga events, so canon divergence. Season 1 and 2 anime spoilers only. Disclaimer: I do not own My Hero Academia or any of the characters. *cross-posted on AO3*