it is used to callsomeone you really love, care for, have feeling for. They are usually very close to you. The one for whom you can sacrifice your life.
Mother: I love you!!! You better not become a cutiepie!!
Son: Whats a cutiepie?
Mother: A pie made of cute little kids... They taste extroadinarily good!
Someone who’s hella cute and you can just describe them as cutiepie. You want to give them the whole world. For you, they’re the most attractive, most beautiful and prettiest human being on earth and they make you happy eveytime they message you.