Wunk
To wunk is when two people have sex on an object. (Bed, table, chair, etc.) Upon reaching optimal velocity the noise being heard from the friction of the bodies moving the object is described as a wunk. Such as a bed squeaking or chair creaking, or when a table rocks across the floor.
They were going so hard at it, that the bed began to wunk.

After shagging so hard on the table, they began to hear it wunking.

She told her friend of the time a male hooker forced himself on her so hard the chair wunked.