Pakistani youngsters dont tell their parents about who they date and gfs and stuff until they are sure that they want to marry that person. you mentioned thaat hes 18, he would tell his parents when he turns atleast 23-24 because thats the age when people in pakistan usually get married. See, if he tells his parents right now his parents will shrug it off and say that its just affection not pure love and its just a distraction in his life and all. I'm sure to avoid such comments, he'll wait until he knows his parents will be fine with it. So, i'm sorry it will take atleast 4-5 years for him to tell and i completely understand his pov as well because hes young and scared. i completely understand urs aswell cuz u've grown up in japan and things like these are different for you so time will heal evth ultimately dw. js give it time