Since their parents were close to each other, their sons and daughters also became friends. They would always hang out when they were still kids so everyone had a very close bond with each other.
When they grew up, they seldom met each other because of their studies. Ayumi and Elijah studied abroad while Kenji entered the military. Allen had become busy assisting his Uncle in managing the company of Sy Corp.
Cassie and Christian isolated themselves because of the threat from guardian warriors. They trained themselves with the help of their parents and Zu Wan.
Because of their schedules, the young ones couldn't meet together. After a long time, they finally reunited here at Allen's house but Cassie and Ella were not around.
Allen somehow knew what happened to the two so he initiated this housewarming party to cheer his cousin, Christian. Besides, Elijah and Ayumi came back from abroad.
