(1) The act of eating a girl out while she is on her period.
(2) When you go down on a girl who is menstruating.

A man who has his first red su dae is said to have earned his red wings.
(1) It was dark yesterday when i was going down on my girl, turns out she was on her period and i ended up having a red sundae.
(2) i told my boyfriend i was on my period and he said he was in the mood for a red sundae.
by Goddest88 August 30, 2019
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The inflamed area around the male crotch that is the direct result of skin disease.
Wow Theo, what the hell is going on around your crotch??? It looks like you got a red sundae going on.
by Dickhead4loife August 23, 2021
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