Denki is rather shy boy as he is not able to stand up for himself saying he wants to stand up to his father so he can study and become what ever he wants to. His personality later changes when he is bitten by a shadow figure becoming more darker causing him to try to kill the gang of boys that were bullying him by setting up prototype trains that would collide into one another but is later saved by Boruto Uzumaki and Denki snaps out of it and comes back to himself helping Boruto stop the train crashing he is more confident in himself after the event when he joins the ninja Academy. Also when Boruto activated his dōjutsu, he saw a purple coloured chakra aura surrounding Denki.
Background
Denki is the son of the owner of the Kaminarimon company. He was bullied by a group of students in an alley where Boruto passed by and helped him. The two immediately became friends and Denki was inspired by Boruto to act on his own and pursue what he wants causing the former to have an argument with his father where a certain unknown shadow overpowered him and "partially" controlled him.
On the way to the opening ceremony of the Academy, Boruto saw Denki and followed him. He learned that Denki was planning to get his revenge from his bullies which surprised Boruto. There, Boruto saw something on Denki and thought it was peculiar. Following on the events on the train, Boruto learned that Denki was trying to collide their already defected train with another train defect. Due to Boruto's words and pursuing, Denki seemed to become aware of what he was doing, just in time of collision Boruto managed to swing the switch to move the train out of another rail and before Boruto might fell Denki saved him together with the bullies. Boruto and Denki then approached the opening ceremony using the defected train causing it to hit with the Seventh Hokage's stone face.
Male
