"The Return to a Distorted Reality"

Prompt: Finally you defeat the Dark lord and earn the right to return to your world after being isekaied to a fantasy realm. You return on the same day you left, exhausted you go to your room to sleep. The next morning you realize something is wrong. Your caring mother has become a hardcore gyaru who only dates black men. Your sweet and innocent sister is now the well-known school slut; she spends most nights working the streets as a prostitute. Your father is seemingly out of the picture. Your long term girlfriend is now engaged to your rival. Only you seem to remember the world before.