A very cool person. Most often a hot male with extreme skills in everything. Often used as a compliment.
Girl: "That guy is so hot and totally awesome, a real koyo!"
Boy: "I wish I was a koyo like that guy."
"You are such a koyo"
Boy: "I wish I was a koyo like that guy."
"You are such a koyo"
by Nick34 December 09, 2008
Get the koyomug.