Quirk knight

Viper is a 18 year old fomer HPSC assassin who has help save the multiverse multiple times while her home universe was destroyed. In the latest crisis Viper had lost her right arm while becoming a night to the princess of quirks

How her boss is planning to retire in 2 years, so she's given one year to learn how to keep her new powers in check by traveling with the princess

However nothing ever easy for a peacekeeper, especially a founding member.