An advanced sexual act, in which the male inserts himself from behind, and then does a cartwheel. imitates the motion of a vault door opening.

keep out of reach of children.
guy 1: man, me and Chrissy got frisky yesterday, ended up trying the vault opener. It ripped my dick off, but other than that it was quite nice.
guy 2: ... Isn't Chrissy the name of your dog?
by DestroyerOfWomans November 10, 2020
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