Anal fingering is a type of anal stimulation that involves inserting a finger or fingers into the anus. Couples can finger each other during foreplay and sex, or it can be done on an individual basis as part of masturbation. This type of stimulation is often very pleasurable since the area is packed with nerve endings. Men will usually find anal fingering particularly pleasurable because it can lead to the stimulation of the prostate, which is the equivalent to a woman's G-spot.