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[–] 9 points 17 hours ago (4 children)

Wait a minute. You're right. Why DOESN'T it get hard when cold like my nipples!? What the hell!?

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  • [–] 17 points 16 hours ago (3 children)

    Because your nipples get hard due to the erectile muscles (same as goosebumps, a holdover from when we were hairier), and your scrotum is constantly adjusting to keep the ideal temp for sperm production/genital function.

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