I found this fatmanfuck video a while ago, this guy has a tight foreskin and this girl quickly pulls down the foreskin to blow him. He had to stop her because she touched his glans and he was too sensitive. Retraction at 2:13, the rest of the video is foreskin up
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The second video is a different girl, we can't really clearly see her retract his foreskin but she does and then proceed to blow him. His reaction clearly shows he's super sensitive.
First retraction at 6:55 with a fart and a laugh??
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Plenty more videos can be easily found online
