If you’ve masturbated before, you know the answer to this question! In addition to feeling so good, masturbating relieves sexual pressure that builds up naturally over time. Every male gets “horny”, and then his mind gets preoccupied by erotic (sexy) thoughts. This is a natural process: Your sex organs produce and build up semen, and your body responds by causing you to want to ejaculate the semen to make more room. One way this happens is through a nocturnal emission or “wet-dream”, an ejaculation during sleep. Another way is through masturbation, where you stimulate the penis to fool it into “thinking” you’re having intercourse.