While your hitting it from the back, pop it in the other hole, with no lubricant, and no warning. When she screams out "WHAT THE FUCK???!!!!" Tell her how good it feels to have something tight wrapped around your dick, and then stick it back in her cooch, and tell her she's fucken loose and it's OVER. Then put your clothes on, pop your collar, and leave. Guarantee you within a week, she'll admit to cheating on you.