In the not so distant future, a powerful company called Skylabs decided to start a new project - one where robots and machines become obsolete, and will be replaced by mecha-organic humanoids known as homunculi. Whether made for war, protection or entertainment, the homunculi are meant to serve the mankind.
Jun, one of the Skylabs programmers gets an opportunity to design his very own homunculus. However, once he finds out who was responsible for the death of his father, he decides to rebel against the corporation. And by that, he steals his designed homunculus and trains it to help him with taking revenge.