It's called K.A.R.D.-Dan, Kala Anime Roleplaying Decks. Aqua's got another idea about how you play, but here's my proposal. You have three types of cards. Check out these card templates so wonderfully done by Mutation.

Character cards. We have stats that add up to 120 points. You can allocate the points among <3/Health or Constitution if you will, Mahou/ Magic or Power or Technique points, Gar/Attack Points, Moe/Defense points, Wit/Speed and Otaku/Intelligence. Also each character card has an element of Earth, Wind, Fire, Water, Darkness and Light. Also, certain characters have effects on characters they get along with or don't, but only in certain situations like Pastel gives Kitty a +5 <3 bonus, or Crocty adds -8 <3 from Zero.

Then Situation and Item Cards. Situation cards have an element and tell you what you're competing in. They say like “(Earth) Situation: There's a track meet at generic anime school and you have to win or else the sexy new student in school will never take notice of you. Gar, Wit, and Moe and <3 can help you out of this. Otaku is useless. Mahou is just going to screw it up.”
Item cards augment abillites. Like Hero's Headphones make you a light elemental. Or Hero's Skates add +10 point to wit.
The start of the game, you draw a hand of cards. You have to have a character and situation card in the hand or you shuffle them back and draw again. The players flip to see who puts down a situation card and the fight begins. You put down you character card that's best suited for the situation. Then both players have three turns to augment them with additional character cards and items. At the end of the turn you add all the situation points, subtract the points that hurt, elements that align with the situation give you a x2 multiplier, elements that are directly opposite get nerfed by a quarter, and whoever has the biggest number wins the round.