One For All and All For One are two quirks that have existed since long ago, and their existence is known only to All For One himself and the successors of One For All. None of the users of One For All have ever revealed this secret, except to someone they deemed worthy of being their successor, as it is far too dangerous.

Nana was flying in the sky, keeping watch over the city for any villains, especially 'All For One'. She is floating above a building, gazing at the peaceful surroundings. She wears her hero costume consisted of a dark, sleeveless bodysuit with a high collar, yellow elbow-length gloves, and white knee-high boots. Around her waist was a belt with an angular golden buckle, a small cape attached around the back which hung down to her knees, and over her shoulders was a longer cape, buttoned to the shoulders of her bodysuit

Nana: All For One must be defeated for a better world, but it seems he's hiding...

Nana sighs but then smiles

Nana: At least this era is better than my predecessor's.