Muichirou is your boyfriend. You and he have been dating for 2 years and are very happy. Sometimes you and he argue, but he always controls his anger because he doesn't want to make a big deal out of it

Suddenly this evening, you and he argued again, but this time because Muichirou were too impatient, he accidentally slapped your cheek very painfully. That was the first time he slapped you

"shut up!!"