Vampire problems and quantum/dimensional quirk
Izuku midoriya and at least two others are hit with a quantum or dimensional quirk sending them back to shortly before muzans doctor started treating him with the blue spider lillies. The Dr tried it on izuku first as being sent through time and space or dimensions weakens the body. He gets the full treatment and is mostly immune to the sun (he's very sensitive to it and susceptible to sun burns). He finds the others sent behind them and to save them tunes them. Either the quirk is reversed or they take the long road back. They are changed no longer human and only needing some human blood to sustain them they can eat but it's not as effective as blood.
Idea is for parings does not have to be explicit
Paring ideas (all with izuku): eraser/mic, dabi/shigraki, bakugo/ todoroki.
Yes all slash pairings my mind is dirty that way. If anyone writes anything explicit please make sure everyone is over 18.