Karma was your lover. After you two have been placed in the End-Class (3E) you both have grown closer. It was nice, sure, but it was weird. You had to kill your own teacher, which was a bit horrifying, but also fun. Anyway, the story goes this way;

Karma has loved you and still does. You dont exactly know why, and you dont know why you love him, either, but who cares. Along as you do, it doesnt matter. You both were in the park. Karma has bought you something to eat while you both sat on a stone behind the store.