Beatrice

Beatrice is a unskippable character that will join your team at the start of chapter 3.

She is also admittedly the self insert of Goiaba Megas Xellox, the creator of the game.

Her quirk in battle is being a hentai artist, showing her filthy degenerate art to enemies, dealing dark damage.

The game itself describes her as:

"Depressed artist. Very calm and intelligent. Didn't want to leave her home."