Mr. Weed was never revealed to be homosexual; however, he preferred the company of men within his chamber quarters, and there are several instances that suggest he was gay. In "A Hero Sits Next Door", after he hires a ringer named Guillermo to play for his company's softball team, Peter says that he walked into the locker room and saw Guillermo "bench pressing" Mr. Weed. In "The King Is Dead", Peter invents Mr. Zucchini Head which resembled a vibrating sex toy. Mr. Weed takes the toy into his office and does not come back out with it. In a scene from "Death Has a Shadow", Peter breaks off the penis from The Statue of David and throws it through Mr. Weed's window. Mr. Weed names it Eduardo and takes ownership of it. In "Mr. Saturday Knight", at the showing of his will for the company, the lawyer accidentally plays a tape of Weed making breakfast in his underwear and being filmed by a male companion.
In "I Am Peter, Hear Me Roar", he collaborates with Gloria Ironbachs in deciding to discipline Peter by sending him to women's sensitivity training.
He was a fan of the Boston Red Sox, as seen in "Mr. Griffin Goes to Washington" when he roots against the New York Yankees.
When Brian asks the ethnic origin of the name "Weed" in "Mr. Saturday Knight", Mr. Weed tells him the name was given to his grandfather when he came to America. He then informs Brian his real name is Bermuda Grass. Mr. Weed died in the Griffin home after accidentally choking on a dinner roll. After his funeral, Mr. Weed left a videotaped will to all his employees. The tape first shows another man videotaping Mr. Weed making an omelet, followed by the embarrassed lawyer fast-forwarding it to the real will. Mr. Weed then surprisingly reveals that the Happy-Go-Lucky Toy Factory is to be demolished in order to make way for the Happy-Go-Lucky Terminal Disease Institute. As a result, Peter and his co-workers all lose their jobs. Peter seems to be hit the hardest, and he struggles for a job for several episodes. Ironically, the dinner was meant to impress Mr. Weed enough to give him a promotion, which Peter received just before Mr. Weed's death and ensuing dissolution of the company.
He wasn't mentioned again until "Lois Kills Stewie". When Stewie is about to execute Lois, he tells her, "Say hello to Cleveland for me. . . oh, and Mr. Weed."
Jonathan Weed was voiced by Butch Hartman in the Pilot Pitch, and replaced by Carlos Alazraqui until the character's death. Alazraqui gave Weed his Hispanic accent.
- FG101: "Death Has a Shadow"
- FG105: "A Hero Sits Next Door"
- FG202: "Holy Crap"
- FG207: "The King Is Dead"
- FG208: "I Am Peter, Hear Me Roar"
- FG218: "E. Peterbus Unum"
- FG301: "The Thin White Line"
- FG303: "Mr. Griffin Goes to Washington"
- FG304: "One if by Clam, Two if by Sea" (mentioned)
- FG309: "Mr. Saturday Knight" (dies)
- FG605: "Lois Kills Stewie" (mentioned)