A person, typically male, of legal adult age that doesn't act his age, but is obsessed with Marvel/DC comics and movies. Most likely a virgin or has very little experience with getting laid and women in general. Typically skinnyfat or otherwise out of shape. 50/50 is fat with a beard and constantly talks about how bearded guys rule or some other nonsense. More likely than not has a "gaming station" with Cheeto dust covered keyboard. A frequent patron of the comic con festivals. Ferociously defends fictional female Marvel/DC characters on twitter from "chads". The older this person is, the more of a marvelcel they are (see 30's, 40's). Probably has a sword of some sort in the bedroom.

The suffix -cel comes from the word incel.

Also synonymous with marvelfag.

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