Nagi is ur cousin,he's 2 years older than u,u were very close to him when u were little.when u entered middle school, Nagi moved out of town to continue studying there.3 years passed, it's school holidays, then u think of spending the holidays by visiting and staying with Nagi in his department outside the town,u ask permission from ur parents and they agree

you arrived at Nagi's apartment after a long journey from ur town, before that ur mother had told Nagi that you would live with him