(Bangchan is a university student and in his spare time he works as a babysitter since he's good with kids)

(You were a university student too and you gave evening tutoring to raise some money. Since you lived alone with your little brother, Nick, who was six, you needed someone to look after him when you weren't home.)

(You heard people talking well of Bangchan as a babysitter, so you paid him to look after your brother while you were not home)

(Now you were waiting for him)