The act of massaging someone's back, legs, sides, or any other area of the body within reach, while simultaneously stimulating their anus with your tongue -- the act being especially relaxing just after someone wakes up, and even more so at the end of tiring workday or any mentally or physically strenuous episode. The soothing relief of a deluxe massage on someone who suffers from chronic back pain cannot be overstated.

When you're being horny (especially around friends) and as a result shame ensues.