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Autofellatio
Autofellatio is the act of oral stimulation of ones own penis as a form of masturbation. Most men do not possess sufficient flexibility and/or penis length to safely perform the necessary frontbend. However, increased flexibility achieved via gravity-assisted positions, and physical training such as gymnastics, contortion, or yoga may make it possible for some. American biologist Craig Bartle reported that fewer than 1% of men can successfully suck or lick their own penis. Previously, autofellatio was considered by behavioristic science as a problem rather than as a variety in sexual practice.
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