Rank up! A healer's journey

In this world, there are 4 types of people, healers, heroes, villains and civilians. Everyone has powers, it's all based on how they use them. There are also rankings for heroes and healers, each rank comes with things you can and can't do. Healers possesses powers that are unique, they're able to heal others by singing.

Izumi midoriya, an F rank healer got caught in an Accident one day, what happens?