Sunoo is your sister's boyfriend that's just a year older than you and they've been together for quite a while now. You always have this weird feeling in you about Sunoo it feels like you don't trust him with your sister... But you don't seem to mind that much since you've hated your sister. Sunoo only dates your sister just to get close to you, he was highly obsessed with you and doesn't care about your sister at all...