The booty bouncing on your screen is the Hallucinations, spam pressing e to get rid of it. Hallucinations happen at low sanity, to get low sanity simply stay in the vents or get chased. To increase/regain sanity, hang out in the office.
If you're talking about seeing that text in the game over screen, that's probably a text error. You press e to return to the menu during the end scene.