Tits moving a rhythmic circular motion similar to that of a helicopter rotor when fucked. Most commonly seen in larger natural breasts it can be induced in smaller breasts provided enough force is applied.
I was so mesmerized by your Mom's helicopter tits that I feel off your race-car bed.
When you take a virgin girl who is your good friend, and she shows you her tits. The person looking at her tits shows her his penis and then moves his penis around like a helicopter and starts saying, "GET TO THE CHOPPA NOW!" This only takes place during school in private.
Hey we should do helicopter tits more often it was really fun!