I can take this one. I'd say that's perfectly normal. It's all about how easily excitable you are. Me for instance, I get an erection for little or no reason. It can actually be really irritating. In class, at work, driving, no reason. I'm not even thinking about sex, it just happens. Being close to a girl physically turns you on enough to get an erection, no shame in that. Perfectly normal.

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Heit ist mein taug.