Despite being a protagonist, Jeffy can occcasionally act antagonistic.
He is also known as Jeffy Jeffy and Jeffy François-Jeffy.
He is voiced by Lance Thirtyacre. His animal noises were provided by Anthony Miller.
Jeffy also appears in Puppet Pals as one of Pink Evil/Pink Awesome's best friends.
Jeffy is dimwitted and likes to put pencils in his nose, putting his pee pee in stuff and spank his diaper. He can easily cry and bang his head on things when he is called a bad boy.
He can also act rude, angry, demanding, and disobedient.
Despite his bad behaviour, Jeffy has a few good deeds such as being considerate to Hansel, saving Santa from choking and stopping Drawing Jeffy. He is most likely misunderstood after being abused by his biological mother and witnessing the death of his twin sister.
Even though Jeffy usually has bad behaviour, he also does some good things.
- In Jeffy Sneaks Out!, he stops Drawing Jeffy (also known as Play-Dough Jeffy) from playing with a gun.
- In Jeffy's Birthday Wish!, he wanted to use a birthday wish which stops everyone dying from the solar eclipse however Brooklyn T. Guy used the wish instead
- In The Diamond!, he helped Mario stop The Robber.
- In Jeffy's Bad Christmas, he saved Santa Claus' life from choking.
- In Puppet Pals videos, he ocassionally saves Mario from floods and fire.
- Jeffy's birth mother, Nancy would be the reason why Jeffy has bad behaviour since Nancy abused Jeffy for no reason.
- Although Jeffy has become a teenager in August 21st 2017, he does not act like one.
- Despite being 15 years old, Jeffy has gotten a cheerio box pregnant and Brooklyn T. Guy helped Jeffy and The Cheerio Box give birth to Puss Hole 1, Puss Hole 2 and Jeffy Junior in Jeffy Has Kids!.