Jeffy

Info: Jeffy Jeffy is one of the main characters of the SML series. He is the adopted son of Marvin and Rose.

He is the biological son of Nancy and Jacques Pierre François, and the older half-brother of Feebee, but ever since he was dropped off by Nancy at Marvin's apartment, he is now the legally adoptive child of Marvin and his wife, Rose. Jeffy also has a clone from "Jeffy's Clone!" named Scooter, who made a second appearance in 2020 after being absent for almost two years. However, Scooter has not made an appearance since "Jeffy's YES Day!".

The things that he does in his everyday life are annoying Marvin, hanging out with Junior and his friends, hating school, causing trouble, making messes, eating chocolate cake, etc.

Personality: Jeffy started as a really unintelligent individual, causing people to believe he is mentally disabled, before changing into a misbehaved person who swears a lot, explodes in anger at any slight against him, and knows a lot about perverted acts for someone his age. He likely does these actions on purpose including the cussing. Over time, he has matured and does not annoy Marvin and Rose as much as he used to. He barely swears anymore and only acts more like a troublesome child. He is also known to be very strong, possibly one of the strongest characters in SML, as he tends to beat up bullies, hit balls hard, and has a high pain tolerance. A good example of the latter is in "Invisible Jeffy!" where he managed to tolerate if not barely endure being shot twice by Mr. Goodman. Overall, Jeffy's personality has gone through more changes than any other character in SML.

He has a habit of spanking his diaper placed outside of his pants as well as soiling his pants often. When he is called a "bad boy", he tends to have a breakdown by throwing his head and hitting it onto any surface but calms down when he is called a "good boy" (this is no longer the case after the events of Jeffy Loses His Pencil!). However, his breakdowns can become extreme and violent, which involves intentionally using curse words and being rude towards Mario and Rosalina. He also flips his desk in "First Day of School!" because the teacher (Who is Jackie Chu) assigned a 10-page essay that was due the next day and cusses (mostly the F-word) at Jackie Chu, saying "ARE YOU FUCKIING HIGH?!". He often says "Why?" whenever someone tells him what to do or what not to do. He even keeps saying it whenever someone answers him. He also has a habit of calling things he likes "pee-pee." He also often answers with "I don't even know" when asked questions.

He likes to put his "pee-pee" in various objects, especially Cheerios boxes, to the point where he somehow even impregnates one and developed romantic feelings for it.

He deeply resents Bully, who picks on him and subsequently beats him up all the time, but the person he hates even more is his teacher, Jackie Chu. His teacher usually gives out ungodly amounts of homework, which gets an awful reaction from Jeffy.

He is also afraid of trivial and ridiculous things, such as animals, toilets, snow/bubbles, ostriches, and the number 7. Based on characteristics, it is suggested that he has a mental disability. His mother brought him to Mario because she did not love him for unknown reasons (according to Jeffy). He also has a fear of water. This is shown in "Jeffy's Bathtime!" when he refuses to take a bath. It is also shown in "Jeffy's Swimming Lessons!" when he refused to take the swimming lessons and would scream when in water. Because he has a huge fear of water he would drown almost immediately. This is shown in "Jeffy's Swimming Pool!" when he drowned in the pool due to his difficulties in swimming.

Despite not being that intelligent, Jeffy has shown traits of intelligence, but in a stupid way at times, such as in "Jeffy's Homework!", where he reasoned that the equation 8-4=8, since they are taking 4 out of the equation, even going on a profanity-laced rant as well as getting very smart over the years as Mario thinks he will not notice anything or remember anything but he does so he is not very dumb anymore. He is also an extremely skilled painter, a trait passed down from his father. He has also shown signs of intelligence, such as in "Jeffy Gets Ran Over!", where he remembers everything that happened to him after getting knocked out by Mario's car, as well as knowing that Mario is the one that hit him.

Jeffy has shown to be demanding and a spoiled brat, even more than the level Junior displays, as seen in "Jeffy's Bedtime!", where he demands that Mario and Rosalina make his green eggs and ham, "Jeffy Gets Potty Trained!" when he demands that Rosalina give him marshmallows instead of peas, "The Hitman!", where he wanted Jello after Mario gave him green beans, he refused to eat his McDonald's Chicken Nuggets because he wasn't given 20 toys and threw them away, in "Locked Out", where he demanded chocolate cake, cried when Mario didn't give him it and locked Mario out to enjoy the cake, especially in front of Mario, and in "Jeffy Gets Help!", when Jeffy yells, screams, and throws a temper tantrum because Mario said that he would not watch SpongeBob SquarePants.

Jeffy is shown to enjoy playing pranks, as seen in "Jeffy's Cellphone!", where he prank calls several places, including a Dominos employee named Josh and a prostitute, resulting in Rosalina thinking Mario is cheating and beating on Mario, and in "Shrek The Babysitter!", where he locks Shrek in the bathroom with the help of Bowser Junior. Both of these videos shows that he seems to be less unintelligent, causing many fans to think that this could be a normal version of Jeffy, despite all of his intelligent moments in the series. Some people think Jeffy pretends to have a disability therefore goofing off and pretending to care about his grades when he doesn’t (including pretending to be mad about it when he isn’t). When his real mother Nancy tries to claim him back, Jeffy begs Mario to let him stay and promises to be a good boy (and keeps his promise by not playing the cat piano when he goes back inside), indicating that he loves Mario very much. Jeffy's obsession with swearing may be from his mother using the cuss words deliberately and the way she acted in front of him and treated him.

However at his worst, Jeffy is infamously known to break out in sociopathic tendencies and engage in several criminal acts and hold severe disregard for the law (which is generally unsurprising, given the majority of the cast have committed several crimes, including murder). It can be argued that Jeffy's condition clouds his judgment and many of his actions are out of impulse. However, even then, Jeffy is willing to commit crimes out of malice, specifically towards people he has contempt with. As such, Jeffy struggles to understand complex situations or the feelings of others, and is often willing to react with anger or destructive antics when things don't go his way.

Despite all this, he is generally more on the friendly side and the bad things he does is mostly due to his unintelligence. He has his fair share of good deeds that outweigh the bad ones, such as being considerate to Hansel in three episodes. He is most likely misunderstood after suffering pain from his biological mother and witnessing his younger half sister's death, which might explain his outburst problems.

As seen in "Jeffy's 20th Birthday!", he went through a lot of abuse as a child, and most likely acts the way he did in his early appearances in order to cope with the trauma that came from his childhood. Therefore, his demanding and misbehaving qualities are somewhat understandable, and can be considered a coping mechanism for Jeffy. It wouldn’t be wrong to say he’s not the sharpest tool in the shed sometimes, but it would be completely incorrect to say that he intentionally means to do harm. He knows when enough is enough and will take full responsibility when he realizes what he did was wrong.

Although he is unintelligent, he is shown to be an adult to Marvin in some episodes such as the time when he caught Mario spilling water all over his bed and Mario wanting to play with his Lego rather than eating his food. And sometimes he does not like to believe people like in "The Halloween Heist!".

Throughout his time in the series, his intelligence has steadily increased, and he is of average intellect as he is able to come up with clever plans (such as in "Jeffy and Junior's Big Heist!") and successfully escaping from his mother in "Jeffy's 18th Birthday!".

Jeffy is heavily hinted to be bisexual and attracted to animals, since he has been attracted to both women and men and has and wanted to have sex with animals and fake animals. He is sometimes kind and can be caring of others around him even if he doesn't show it much

Appearance: Jeffy is somewhat different than the average young adult, with a tall and slim posture. He wears a blue bicycle helmet (with dark brown, messy hair under it), usually has a pencil shoved up his nose, has blue crossed eyes, and wears a yellow T-shirt that reads "Jeffy" on it which his mother wrote so he would not forget his name. When a different word is written on it, he thinks his name is that word as seen in "Jeffy's Shirt!" when Junior wrote "poopy butt" on it, making Jeffy think that it was his actual name to the point of losing 100,000,000 dollars because of it.

He wears short dark blue jeans with a Pamper diaper (which, according to Jeffy himself, is on the outside so it doesn't get dirty), which he occasionally spanks. He wears black Adidas sneakers with black shoelaces. His biological appearance seems to be mixed between his parents, with his blue eyes possibly from his grandparents and his dark brown hair inherited from his father. His face is oval shaped with two teeth and around the nose, along with two eyelashes and a unibrow. Jeffy's jaw has minor damage to it due to it making ugly faces, despite this, he is still very strong in muscles which he claims is "chromy strength".

Jeffy’s personality is just weird.