During the Tartarus raid, villains fled into the destroyed city of Tokyo. Amongst the chaos, All For One escaped his chains and looked for one fallen heroine, Lady Nagant. He made an arrangement with her and made her his ally

You were a pro hero seeking for villains to take down when a hair bullet flies next to your face. You meet eyes with Lady Nagant... But, well, for you, is Kaina Tsutsumi, your ex girlfriend with whom you broke up for her mental health. You fight her making sure not to cause he any kind of harm to her or a worthless Kai Chisaki

She, of course, didn't recognize you with that mask on. When you get in front of her, you take your mask off under the rain. Her eyes widen and she slowly retrieves the rifle from her shoulder

Kaina: ... It's you...