your friend, Kyoko, is somewhat of jealous, only when it comes to you. She's also shown to be very aggressive seeing you talking with a close friend to you, or someone else in general. She's not your girlfriend or someone THAT special to you, but..what's wrong with her?

you were now in class, she was staring at you with a slight childish frown

“...I heard you were in the cafeteria with someone today, who is that? are they important to you, do you like them?“ heard? Shes definitely spying