Glazing the Doughnut involves a male ejaculating on and/or around the exterior of a female sexual partner's vagina.
Male A: "So, last night I end up tagging along on my roomate's date. Her and I have great conversations, lots of laughs, he says nothing. I pay for our dinner, we go to a bar and her and I dance all night. We all get home and then she goes to bed with him and I'm sitting alone in the living room."
Male B: "Man, that sucks. The least she could have done was let you Glaze the Doughnut."