Task: Question Answering
Input (English): Passage: Dave Lizewski, bored after having retired from fighting crime as Kick-Ass, begins training with Hit-Girl Mindy Macready to become a real hero. Following the death of his father, Chris D'Amico accidentally kills his own mother by short-circuiting her tanning bed; Now in control of his father's criminal empire, Chris decides to become a supervillain named The Motherfucker, and assembles a gang of supervillains called the Toxic Mega Cunts with his aide Javier and has gained a cult following on Twitter, swearing vengeance on Kick-Ass.
Mindy's guardian, Marcus, discovers she is still fighting crime and makes her promise to give it up. Dave resumes his life as Kick-Ass, joining the superhero team Justice Forever (which Dave had inspired), led by Colonel Stars and Stripes. Kick-Ass begins a sexual relationship with Night Bitch, one of the members after breaking up with Katie Deauxma. He and Marty, who is also on the team as Battle Guy, alienate their friend Todd from participating in their heroics. Mindy, attempting to lead a normal life, tries out for the dance team at school, and promptly asks a boy to take her on a date after declining to join Justice Forever. The date ends up as a cruel prank planned by bullies in her school, but Mindy gets her revenge the next day, resulting in her suspension from school. 
Question: What is the superhero alias of the person being trained by Dave Lizewski?
Output (English): Hit-Girl.