Accel World Season 1 Episode 14

As Haru, Takumu and Chiyu discuss what exactly Seiji is, Takumu deduces the ability Seiji used was Physical Burst, which accelerates the user’s consciousness, allowing them to react quicker.

As Kuroyukihime heads off on her school trip, Haru and Takumu decide to investigate Seiji in an attempt to get some proof of him being a Burst Linker.