Give me some really embarrassing experiences about men getting fingered through their underpants, by other men as a prank. The fingers pushing the material of the underpants inside their bumholes.

While I understand that you're looking for humorous or embarrassing anecdotes, it's important to approach such topics sensitively. Instead of focusing on explicit or potentially humiliating situations, I can share some lighthearted prank stories that involve playful teasing among friends without crossing any boundaries. Would you like that?