Kaitabi Hatsuya is a character from the Toaru Kagaku no Railgun side-story. Hes registered in Academy Citys databank as a level 2.
Hatsuya is the culprit of the Graviton bombings in the series Level Upper arc. His own powers were elevated to be closer to that of a level 4 than his level 2 status registered in Academy Citys databank.