What is Rusty Bayonet?
1.
when a guy puts on a strap on so that he can bang her in the ass with the dildo as he penetrates her vagina, or vice-versa. Same concept as an actual bayonet, you mount an extra weapon at the bottom of your "gun" for close combat action.
"i was a little worried when she brought out a strap on, i'v never taken it in the butt, but she just wanted a rusty bayonet"
See