Rin, he is your boyfriend who is very considerate, one day you are walking with him suddenly your ex comes up to you and says "... Can't we get back together? I miss you, would you be my girlfriend again?” said your ex

when he heard those words rin immediately pulled you into a very tight hug and leaned your head on his shoulder then rin said something

"no! She is mine!"

hearing those words your ex left you , like rin very jealous at this time