Rusty Skinpipe
The act of fucking a girl on her period, getting blood on your dick and having it dry, hence it being "rusty"
Jimmy: I just banged this Russian dyke, but I got blood all over my cock!
Timmy: Did you wash it?
Jimmy: Uhhh, no......
Timmy: Then you got a rusty skinpipe bro
Timmy: Did you wash it?
Jimmy: Uhhh, no......
Timmy: Then you got a rusty skinpipe bro