Shun Asanaga and Emilio Langheim could hardly be more dissimilar from one another given their respective rise to prominence in different worlds. Shun is a 15-year-old upperclassman who has been appointed and is very optimistic and kind, in contrast to Emilio, who just turned 16 and has only one thought in his mind: revenge on the amenable King Delzain. Shun one day finds a mysterious crystal in his father's office and returns to the kingdom of Endra as a result. Emilio is currently being held in custody after attempting to kill the king in order to obtain the desired revenge. Shun abruptly confronts him with two options: continue the fight with Emilio or return to his own world. What is Shun going to choose?