The act of screenshotting a friend's snapchat picture and/or video because you are a shit person. Often used by shit people for incriminating/embarassing purposes.
Becky spent all night screenshitting snapchats of Fusco to ensure he never forgets the night he passed out drunk because she is shit.
When a girl, while giving you a blowjob, sticks her fingers up your anal passage and knees you in the face and your body orgasms purely from unexpected shock.
Daniel: Jesus man, why do you have a black eye? Thought you were on a date last night.
Eoin: I was with Claudia last night, things got pretty heavy and she ended up screenshotting me. I didn't even know what was happening until it was over. I think I'm in love.