Replying to Parents having sex ?

so its a good night i was chilling with my girlfriend and then my parents say their going to happy hour, allright fine, cool. me and my girl friend leave and go see a movie. i come back and i hear my parents fucking in their room i keep hearing sex noise, and my mom yells bang me like a hammer, im falling off the bed, balls slapping against a vag, ect. its so wrong and gross, i was gonna walk in but naw i came downstairs becuase i got sick of it. and thought id had to tell NS to get someone to laugh. any similar storys anyone ?