But a rubber willy can feel nice
Yeah I get what you mean. THis is supposed to be a GIMP site, but I think of it as a BDSM site.
But I would add, being unable to move, in a stress position, and made to cum repeatedly... It isn't a case of "Oh yes, please more" it is "JESUS FUCKING CHRIST PLEASE STOP OH GOD ANOTHER ONE YES FUCKING HARDER PLEASE HARDER JESUS FUCKING CHRIST PLEAST STOP OH GOD NOT AGAIN ANOTHER ONE YES FUCKING HARDER THERE DON'T STOP DON'T YOU FUCKING STOP OH GOD PLEASE STOP NO MORE I CAN'T PLEASE PLEASE PLEASE OH GOD YES..." etc...
Humiliating, brain melting, really stresses the muscles. But yes, I understand, not especially GIMP.