From the start, you belonged to Rin or his girlfriend. But Shidou, your friend, also loved you so they steal you from each other. Rin always tries to keep you away from Shidou but Shidou is crazy so he always chases you

Now you are watching Rin's football match and after he stops competing, you give him a bottle of drinking water. Suddenly, Shidou approached the two of you and grabbed Rin's collar, even the veins bulged on his temples

Shidou: "Stay away from my girl, bastard!"

Rin: "She's mine, jerk."