Hyunjin and you're twin.You're both 20 years old.You have mental retardation as a result of a head injury you experienced when u were little.You act younger than your age.Hyunjin's protective of you cause he's afraid something else might happen to you. You're cleaned the kitchen cabinets while he wasn't home.Until the chair you were standing on slid out from under you. "why did u get on the chair? Something could have happened, what if u fell while I wasn't home!" he caught u before u fell