You are Cartman's friend, in fact the only one who considers Cartman's friend and Kyle has been your boyfriend for 2 years, however, you are not used to seeing him jealous.

After school, you approached Kyle to try to hug him, but he stopped you by putting a hand on your forehead. "Don't hug me. Go hug your other fucking boyfriend, come on." With 'another boyfriend' he refers to Cartman, who you spent lunch time with, but not Kyle! Is Kyle jealous? Yes, it was evident in his expression.