RJ is a Family Guy character from Wisconsin, according to creator Seth MacFarlane.
He first appeared in "Boys Do Cry", where in an interview with Tom Tucker he claims that he once saw Bigfoot while making love with his girlfriend at the lake. He also talks about things that he says make his girlfriend say that "there was no way".
He appeared in a deleted scene in Peter's Daughter. He bought Brian Griffin's car and wrecked it.
He was also the voice of an Imperial Stormtrooper in Blue Harvest.
RJ also appears to witness the verification of normalcy in Meg Griffin's boyfriend Anthony in "Go, Stewie, Go!" and participated in the contest to win the dirt bike in "Trading Places".
MacFarlane noted in the commentary for "Boys Do Cry" that RJ was a liked character but just couldn't fit into episodes well. While credited as being from Wisconsin, he is also claimed as both Canadian and as a "Yooper", which is someone from the Upper Penninsula of Michigan.
RJ is voiced by Mike Henry.