Scrotum in relaxed and tense states of a Southern European male, 30 years, with semi-shaved genitalia.
<p>The testicles are inside the scrotum, a bag dangling outside the mammalian abdomen, as they need a lower temperature than that inside the body. They usually differ slightly in size, and one hangs lower than the other. At normal temperatures the scrotum and testicles hang very loose, they retreat towards the body as the scrotum contracts for various reasons (cold temperatures, sexual arousal and/or climax, embarrassment, or simply without any reason ...). It is not possible to control the movement.
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