Kiseki is Tadase's Guardian Character. He looks like a mini Tadase with different-colored hair. He is extremely egotistical, loves to dominate, but also has tsundere characteristics. He is always trying to outshine Yoru. His bearing is that of typical "king's fashion", complete with crown and mantle. Kiseki also occasionally calls meetings that require all the Guardian Characters to gather. In volume one, Miki seems to have a crush on him, saying he is cool. Kiseki likes to give orders but does not like to obey. Suffers from pollen allergy like Tadase.

Kiseki can do Character Change with Tadase. When this happens, Tadase gains a golden crown and king’s scepter. The only reason he usually Character Changes is to help Tadase become confident and if Tadase is called "prince".

After the "Black Diamonds" incident, he became able to Character Transform with Tadase. Tadase becomes "Platinum Royale" and used the special skill "White Decoration", a skill thought to be a restoration skill.