1 definition by nameisusedbysomeoneelse_lame

A sexual position similar to 69. In 63, the girl is on top, and instead of giving the guy head while he eats her out, she lets him titty fuck her. The outline of her boobs is like the number 3.
Girl #1: wow did you 69 him last night?
Girl #2: nah i was feeling a little lazy so we did some 63.
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