Anna Scervino is a major character from Boku no Hero Academia the Movie 4: You're Next.
Anna is a young woman with waist-length light peach hair and blue eyes. Upon each activation of her Quirk, her hair begins to darken starting from the roots and then begins to spread until it completely envelops her hair.
Anna is a frightened and saddened young woman, having suffered a great deal thanks to her Quirk that has been causing her pain, and has been pursued by the Gollini Family mafia. This has made her seek for desperate solutions such as getting a Villain to help her escape, or even requesting Giulio to kill her so that she would not lose herself to her Quirk. Much of this is due to the backlash of her Quirk which causes pain to those incompatible to it and additionally gives her painful seizures. In her youth, she was practically emotionless and isolated as recounted by Giulio.
Anna's Quirk is "Overmodification" which allows her to modify the Quirk of whoever is touching her, as long as the subject is compatible. It is able to boost the strength of Quirks in their current state, as well as grant new abilities to their users. If the person is incompatible, they will be met with a sharp stinging pain, temporarily subduing them. Those who are incompatible with the Quirk far outnumber those who are compatible.
This Quirk is always active and causes the user to suffer from seizures and extreme pain after a certain period of time. When left untreated, Overmodification can completely overtake its user, increasing the ill effects and range of the Quirk's activation. This also causes the Quirks of compatible users to evolve to heightened and uncontrollable degrees.
In the anime, she is seen in episode 156 among the evacuees in U.A.'s residential area, now wearing a simple, white dress with wide, frilly sleeves.
