One who, whilst playing Mario Kart Double Dash as a team!, will shoot you with a blue tracking shell right before you complete the longest cup in the game thereby making you come in second place and lose by one point.
AKA: Your little brother
Shootee: "Yes we're gonna win!"
Shooter: "Can I throw this blue shell?"
Shooter: "Okay." *throws the shell*
Shootee: "Omg! You just made us lose! That was a long cup!"
Shootee: "Good going Captain Pants!"