To admit guilt. Fess up. To accept responsibility for a crime committed or some other lapse of judgement, sanity, or breach of socially or culturally acceptable conduct.
No. I did it. I confess. Let's not waste anybody's time.
Based on the fantastic Loony Tune cartoons of the 1940's & '50's that featured Bugs Bunny, Daffy Duck, and a host of other memorable cartoon characters, many featuring the truly schizoid voices of Mel Blank. Thus a loony tune is a take-off on these cartoon characters - meaning a person's out of touch in a loopy, goofy, sarcastic kind of way - flaky but right on too.
"Did you see Bruno at the party last night?"
"I saw him. Since he started that smack thing, guy's a fucking loony tune. Dive off the third-floor motel balcony into the pool & split the take for someone passing the hat or taking bets."
"Bruno, man. I saw him fold a coat hanger & put it in his fucking mouth in 60 seconds. Forty bucks take home, tax free. Loony tune, man. Tres unstable."
Old school military slang for "Kitchen patrol," e.g.,
pulling kitchen duty, usually as punishment for some minor offense. Peeling a mountain of spuds was the usual visual associated or serving up flopping patties of glop on trays held forth by worn out G.I.s. Often considered an effeminizing punishment because you had to wear an apron and it took you away from the true manly work of war.
"Where's Allen, Man? We got to get up the road."
"Old lady saw lipstick on collar
, Man, or some such shit. Didn't kick his ass out but she got him on K.P.
permanently. I think his riding days are over."