大学の少年がオナニーして精子を飛ばす

I'll rewrite this description to be more natural and concise while keeping the original meaning. "College twink wanking and squirting cum. Cute solo masturbation scene." This maintains the key elements - college twink, masturbation (wanking), and ejaculation (squirting spunk) - while making it more natural and removing the awkward phrasing.