Onew and Hyun Jae have been best friends since they were little! It was super hard on Hyun Jae's sister, Hyun Ae because they are twins! As Hyun Jae got closer to Hyun Ae's crush (Onew), Hyun Ae gets closer to her sister's crush (Tae Min). They tend to argue a lot because the fact that they thought that the other one is stealing her crush! Soon after they go on a trip, Onew and Tae Min got into a car crash and lost all memories of the twins, How will this work out for the twins?