when a guy carves a hole into a pumpkin, then he puts his penis in and out of the hole until he jizzes.
Jack had pumpkin sex last night and the jizz was over-flowing.
when two fat/obese people have sex and/or attempt to have sex (even be means of "the oral nature." thank you Bill Clinton).
That elephant-like woman (Roseanne) and that 350-pound man (John Goodman) are going to try to rock the bed springs all night long by having pumpkin sex if one of them does not have a heart attack on the way home.