My Hero Academia: "What makes a Hero" (Fanfic)

What if Tomura Shigaraki wasn't the only one?
What if there was someone else-hidden from the world, trained to destroy, but meant to protect?

Meet Hikari Shimura-Shigaraki's secret twin. Taken by All For One, shaped into a living weapon, and gifted a second Quirk: Regeneration.

Her training was so brutal, she can no longer feel pain.

But now-she's escaped.
Her powers are sealed.
And she's enrolling at U.A. as a "quirkless" transfer student.

Her goal?
Find her brother.
Uncover the truth.
And maybe-just maybe-save him from himself.

Dark pasts don't define you. The future you choose does.
With the help of the friends will Hikari bring light to Shigaraki's darkness... or will they both be consumed?