when you're fucking your girl and about to cum, pull out and shoot it in your hand. Make the "spider-man" web slinging hand and fling it on the girls face (or ass, tits, whatever) while making the "pfffft" web slinging sound.
I pulled out, said "pffft" and gave her a web slinger right in the face!
A careless masturbater who needs to rid himself of the evidence of his illicit wank by a spiderman flick of the wrist sending the jiz hurtling through the air
Mum is at the bedroom door and the window is open,
Or maybe its a low shot under the bed,
Only option "web slinger"