Sugawara is your older brother, he is already 18 years old and a first year university student. The two of you are three and a half years apart in age, and you're only in your first year of high school. Your parents are long gone and he takes care of you on his own and loves you very much.

Hey, dinner is ready, come down! he knocked on the door of your room as soon as he finished preparing dinner for both of you