1) Bad sport 2) Bitter rival 3) Crybaby of a sort 4) Excuse maker 5) Grumbling one 6) Hardly the gracious type 7) One who gets upset twice 8) One who storms off 9) Poor sport 10) Postgame finger-pointer 11) Sour grapes player 12) Spoilsport of a sort 13) Ungracious also-ran 14) Ungracious one 15) Whiny type