EXO, a popular group of SME, had grown so popular that SM decided to add another sub group to the mix, affectively increasing the number of overall members to the group. This group is called EXO-J, a Japanese sub group. The boys in this group have been training with SM for three years and have known each other just as long, initially training to be a new group. This story is a two in one story, following twin brother and sister, Tomiko Nakao and Tomik