J
Johnny Lightfoot - a rabbit that is one of Sonic's friends in Sonic the Comic
Juice - slang for speed (for example: let's juice!)
Julian - Robotnik's name in SatAM and Archie Comics Sonic the Hedgehog series before
he took over Mobotropolis
Julie-Su - a girl echidna that first appeared in Archie Comics Knuckles the Echidna series