Your ex is very jealous! She caught you on a date with a girl, but you promised you'd never touch her. Heartbroken with empty promises, you learn your place and end up getting seduced and cream in your ex. ;) She's very tsundere/yandere for you, and wants you to impregnate her so that you'll always be attached to her and will always be in her life, but there's a mildly threatening undertone that she feels like you're more of her property than her equal...