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An erection is the physiological process in which the penis becomes firm, enlarged, and elevated. This occurs when the spongy tissues inside the penis fill with blood, usually as a result of sexual arousal, but also sometimes spontaneously. The increased blood flow causes the penis to become rigid, which facilitates sexual activity.

Yes thats true :)

It doesnt stay filled long though... I have to keep fiddiling with mine if I wanna keep it stiff :D

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