What is the kinkiest sh*t you've ever done?

when i was 16 i heard my mums bf fk her roughly in the living room,it turned me on so i went downstairs at the end and after hearing her moans and screams saw her run upstairs in tears, i weirdly got hard and her bf saw it, he told me how he fked her then sucked me off until i cum in his mouth, some total fucked up shit right there