A combination on the Rusty Trombone, (a sexual position in which a girl licks the man's asshole while giving him hand relief from behind), and The Blumpkin (a sexual position in which a man takes a dump and simultaneously receives oral pleasure). A modified toilet or a lot of creativity is required.
I received a quite satisfying Rusty Tromblumpkin last night!
I wish I had time for a Rusty Tromblumpkin!
Rusty Tromblumpkins are quite addictive!