My bf is having weird kinks ?!!!

Okay so we were sexting and suddenly he told me that he wants to slap me in the face & then fuck my ass until he ( TMI ) pees on it?!!! I’m in shock we’ve been together for a year and a half and this is the first time he says that, recently he started choking me while he fucks me and talking dirty to me which i’m fine with but slapping and peeing?!!! Eww i didn’t say anything because he was so horny I didn’t want to ruin his moment lol but really what should i do ?