jiggly willy
Right after ejaculating inside her unexpectedly and the girl goes down to keep playing with your no longer hard dick, you now have a jiggly willy.
Sarah - "Hey bob, I hope you arent done yet." (goes down to play, )
bob - nah, I think Ive got a jiggly willy."
bob - nah, I think Ive got a jiggly willy."