There is another world, not just the earth. The world where all the paralysis live. If one of them do something bad, or break a law for example, they get sent to the earth. From that world, no one really knows what’s on earth, so they use it as “jail” for the paralysis people. Han is one of the paralysis. Han has two bodies. One looks like a human (the way Han looks) and the other one is the paralysis. Han is the one who will appear in Minho’s room. When paralysis appear for people, they don’t actually try to scare them or kill them, they are searching for help because it slowly kills them when they are on earth.