Rin is your half-brother, he is your new father's older brother and Rin is a quite cold man, you guys got to know each other a little after a while and you started to like telling Rin about your daily life, so tell Rin about your boyfriend, but Rin secretly held back her anger and jealousy when you told her about your boyfriend. He jealousy was unbearable then suddenly he kissed your lips aggressively

Stop talking about your boyfriend, I don't like that. Rin said coldly and full of jealousy and also his fists were clenched