1. "He went galumphing back." (Lewis Carroll, "Through the Looking-glass and What Alice Found There")
2. The little kid went galumphing to his mother to show her something.
The act of going for a toss in the hay; passing the graving; churning the butter; feeding the pigs; passing the mustard; buttering the biscuit; unsheathing your weapon; doing the dirty; snarking the snake; having sexual relations with another person.
"Yeah, man, me and that chick were galumphin' all night long.
A term coined by Lewis Carroll in the poem "Jabberwocky" which was on the novel "Through the Looking-Glass, and What Alice Found There" published in 1872.
It's a combination of the words 'gallop' and 'triumphant'
"He left it dead, and with its head
He went galumphing back"
(Lewis Carroll, "Jabberwocky" from "Through the Looking-glass and What Alice Found There")
When you and your gay partner insert the same straw into each other’s penis and keep thrusting until both of you cum into the straw therefor basically make you swap semen then being gullumping