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a melted marshmallow is when a dude gives you a heavy blowjob, and you cum such a suprising amount (oh yes, you do it guy on guy, i know you like that) and your excess sperm drips out of his mouth like a melted marshmallow.
you give a guy head, he cums all over your mom's carpet, looking like a melted marshmallow.
by Mallow-King October 19, 2009