He is the 7th Level 5 Academy City student thus making him one of the most powerful espers in the city. Despite being a level 5, his ability is unknown. His rank as the 7th level 5 may not be reflective of his true capabilities since no one understands his power. He is nicknamed Attack Crash after his signature attack.
His personality is not unlike Kamijou Touma, though he is considered hot-blooded and dives into problems headfirst without considering the consequences as shown through the encounter between Gunha and Ollerus, where he misunderstood Ollerus' intentions.
He is also somewhat dense in certain situations, as shown in the Toaru Jihanki no Sonzai Shoumei light novel the first thing after being shot by Mikoto's railgun is commenting that gaming tokens aren't supposed to be taken outside arcades, and that he'll go back with her to return it and apologize.
He also appears to have a habit of giving completely impossible explanations for the nature of his abilities. For example, his explanation for what he does when he executes Attack Crash is that he creates an unstable field of psychokinesis in front of him and destroys it by providing a stimulus from his fist, thus causing an explosive aftereffect for some distance, something which a nearby student in the Power Development Curriculum for telekinesis says is impossible. Also, he explains his Aurora Guard as him lifting Earth's electromagnetic field and using it to defend against Electricity-based attacks, another impossible phenomenon.
In the SS2 of Toaru Majutsu no Index Light Novels, it was revealed that he is a "Gemstone"- espers who gained their powers without going through the Ability Developement Program of Academy City. Thus its unknown to all what his real ability is.
