A mantacorn is a strange hybrid between a Manta Ray and a Unicorn. This animal only exists in strange LSD-induced dreams, and in the minds of young children!
a mythical male creature who is successful (read: pursuing his passion and can pay his electric bills/rent), funny, chivalrous, masculine (read: not chauvinistic), adventurous, artistic (read: not suicidal).
See any John Cusack film (or Chuck Klosterman's witty commentary on Fake Love in Sex, Drugs and Cocoa Pops), any romantic comedy where the flawed guy comes through in the end...
"Where is my manicorn? I keep going out with all these losers!"
"Too bad I settled when I got married, I just met my manicorn."
The elusive perfect male. He can be found at bars, but not singing karaoke drunk while making out with your best friend. He is sensitive to your needs and is a caring man who will put your needs first. He will talk about feelings with you and will never cheat on you ever.
Sean is my manicorn, he is sensitive and caring, he makes me dinner and then we talk about our feelings while watching a romantic comedy and crying at the really happy or sad parts.