^You must not watch a lot of porn because it's been my experience that it's fairly rare for women to keep their tops through their entire scene. Most often than not top wearing tends to be used when the performer has a significant amount of ink or large tattoos and the producer feels that a top is a better option than letting us see the ink. In fact I would argue that women in porn today tend to start with very little clothes on and lose them fairly quickly. The only exception that I can think of is Bryan Gozzling's Hookup Hotshot but I think it's part of is schtick to have his models keep their tops on.

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