A raspberry delight is the surprise application of a raspberry to passing testicles.
"Remember yesterday when Joe's dacks fell down when we were partying at Lucy's place?"
"Oh yeah?"
"Well, I gave him one helluva raspberry delight!"
"Woah! Did you use tongue!?"
"Fuck yeah, Mason mah man, I was like gobble-gobble the turkey fucking king!"
"Shit yeah, Dr. Ferengus, man I'ma gonna havta drop my dackio-panty-cake-snacks right in your face sometime for that raspberry juicy delightness!"
"Hold on, pally-wal Mason-face, lemme pucker up!"
"Toot toot! I'ma like range roving Thomas the Tank Engine with testicles! Boyo my raspberries are so delighted!"