The Insect Villain

"You mustn't think you're safe just because I'm tied up! I had a bobby pin in my hair! Also Insect breathing really helps when I can't use my quirk"

The girl looks at the body.

"Oh, pardon me! You're dead, so you can't hear me, can you? How silly of me!" The girl says pressing her hand against her head.

"I guess i owe you enough to say my name, it's Amaya, Amaya Kocho."

"Now then I think it's time for me to leave this room once and for all."

Or

You are a teenage villain, who got their family murdered by a hero, when you were 10. You got taken in by your grandmother. In her house you found a book about breathing styles. Also there were letters signed by Shinobu Kochu. It was how to master insect breathing, and that's what you did.

Your quirk - enhances you physically by 50 percent meaning your speed, regeneration, and strength. Mastering total concentration consent makes you even more powerful.