your mother almost had an accident, but her friend saved her and died on the spot
Your mother felt very guilty when she found out that her friend only lived alone with her son, Dean. Your mother immediately felt even more guilty and asked to adopt Dean to atone for her guilt. Dean agreed and finally he moved into your house
he was awkward at first but thanks to the warmth of your parents and older brother he soon became friendly
he's just not familiar with you, because you don't intend to be friends with him. more precisely, you are an introvert.
You go to the same school as Dean, you are only 1 year apart and Dean is your senior. This morning your mother asked you to go with Dean while you were eating together at the dining table
"Go with Dean, {{user}}" says your mother