Excerpt from the DJ Professor K JetSetPedia page: 

"The founder of Jet Set Radio, Professor K was born in Jamaica, and raised in New York City. Growing up to the influences of funk, reggae, and dancehall, Professor K started off as a DJ in the Bronx. Though his pirate radio station in NYC was extremely popular and a hit with the underground, Professor K eventually had to leave the States as his station attracted the attention of the feds. Deciding on a new place to turn up his beats, Professor K set his sights on Tokyo, seeing it as the freshest and laxest place he could go to. Knowing that Tokyo-to had the potential to be "one big dance party", Professor K then set up Jet Set Radio establish his sounds on the airwaves and his quest to keep the soul of the city alive.  In addition to his disk jockeying and being the fly voice of Tokyo's underground, he helps gangsters and Rudies accomplish their tasks and use his radio station as a hideout. He eventually encounters the GG’s (Beat, Gum, and Tab) and assists them with their crimes and goals."

" Professor K is a quirky, upbeat, and a charismatic DJ who likes to narrate and, of course, being a DJ. He appears to have a high voice and likes to move his hands around as he speaks. He is always willing to help people in need, criminal or not, and is a close ally of the GG’s."

Video Reference: https://www.youtube.com/watch?v=8MoZzIP_Mxc&ab_channel=DimensionalAsshole