Shit Ballerina
The act of raising one's knees while on the commode, leaving only the tippy-toes on the floor. The resulting position resembles a plie squat with feet in pointe, and isolates nerve endings in the sphincter to provide heightened sensation. This technique is preferred by those who enjoy butt-play as part of sex, especially during masturbation.
Spencer's boss complained about the amount of time he spends on the toilet, until Spencer explained he's a shit ballerina.