The expression that is achieved when a man lies to a female about his penis size being small but in fact it is not, flabbergasm happens at the beginning of sex when the man inserts without showing his actual size achieving a flabbergasted expression on the females face.
My tinder date thought I was 3 inches little did she know I was 8 inches. You shouldve seen her face when I first put it in, she had a flabbergasm.
The act of giving a fellatio laying on a bed/ couch while on your back. Your head is off the side and the male stands over you while his penis is fully inserted down your throat, touching your gag reflex while his testicles are draped and covering your nose and eyes.
Dude, you should have been there last night, I flabbergaggled her till she almost passed out.