What is Slapper-jack?
1.
A sexual act in which the male slaps his partner in the face with his penis as he is ejaculating. The action may include using the penis to rub and smear the semen all over the partners face. The action continues until the male has finished ejaculating and the penis begins to relax.
"Dude, my girl gave me a blow job last night and I slapper-jacked her face so bad she looked like an albino by the time I was done!"
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