D-day capacitor
The secret brain room that only ladies have (usually) that saves every dumb thing your partner does. It waits until D-day to hit you with all the stupid stuff like a punch in the face.
Her capacitor had enough of him calling her 'baby' 20 times a day.
He thought he could get away with it, but D-day came and the capacitor hit him with everything.
That capacitor was full of dumb stuff. He even used her as a footstool.