Definition: In this task, you are given a Reddit post as a text. Your task is to generate a title for this text. The title should start with "TIFU by", followed by a situation that caused humor. The title should contain 7-12 words, ideally.
Input: Text: so this happened about 3 weeks ago, i was meeting my long distance boyfriend who lives quite a long ways away. i have always joked with him that when we meet, i would slap his ass as he hugged me. we have a joke with people slapping/grabbing other people's butts, i know it's really strange but it's just something that we talked about one late night. anyways, i arrive at my destination, i'm in the baggage area to find my bag and i see the back of what i thought was my boyfriend. so me in all my stupidity, runs up behind him and lays a giant slap on this guy's behind. he turns around and swings at me. at this point i know i fucked up, and can't think about the fist coming towards my jaw. so he punches me, as i'm turning the brightest color of red possible and instantly says i'm sorry. i'm clutching the side of my face trying not to cry of pain and embarrassment. i manage to mutter an i'm so sorry for everything and find my bag located on the baggage claim machine. i get up and grab my bag and stand outside waiting for my boyfriend to pick me up. when he gets there, he asks me eat happened to my face and i explain to him everything as we drive to his place. my whole trip, he kept bringing it up and reminding me of the embarrassment i felt. it definitely was not the highlight of the trip.

TIFU by slapping a stranger's ass