Balloon Boy is a human-like animatronic with a round body, peach-colored skin, large, blue eyes, a brown triangular nose, red-brown hair, and a toothy grin. Like the "Toy" animatronics, he has rosy red, blushed cheeks. BB is notably the smallest animatronic in the series. He wears a red and blue vertically-striped shirt with two black buttons down the middle. The propeller cap he wears also bears the same pattern. He wears blue pants and simple, brown shoes. In his right hand, he holds a red and yellow striped balloon, and in his left hand, he holds a sign that reads "Balloons!".
Behavior
BB will not begin moving until Night 2. He starts in the Game Area and will eventually come to The Office via the Left Air Vent. With each of his movements, the player can hear him saying "Hello," "Hi," or simply giggling. BB will not show up on any cameras except the Game Area and the Left Air Vent, keeping his path of approach hidden. He will not enter The Office if the player puts the Freddy Fazbear Head on while he is in the Left Air Vent's blind spot. If the player pulls up the monitor while BB is in the Left Air Vent's blind spot, he enters The Office, laughing constantly. Once inside, he disables the Flashlight, as well as the Left and the Right Air Vent's blind spot lights. This leaves the player susceptible to being attacked by Foxy, as well as being unable to check each vent's blind spot for other animatronics. Once inside The Office, BB will not leave until the night ends, should the player survive.
Trivia
Although BB is often a nuisance, he is not aggressive, and is the only animatronic who doesn't directly attack the player. Thus, he is the only animatronic without a jumpscare.
BB is the only humanoid animatronic in the series.
BB is the only animatronic who speaks in full words, with a non-distorted human voice.
When he is in the Left Air Vent, the balloon and sign he holds disappear. He appears to somehow retrieve them when he comes into The Office.
BB is one out of two Toy animatronics whose endoskeleton eyes never show, with the other being Toy Bonnie.
However, there is a rare chance that upon death, Toy Bonnie's eyeless screen is seen, making BB the only Toy animatronic to bear their real eyes all the time.
Out of all the animatronics, BB can stay in the player's office the longest.
It is possible that BB's constant giggling and talking lures the newer animatronics into The Office, since Phone Guy mentions that they are attracted by noise and move toward where the people are.
BB is the only animatronic that doesn't appear in the Death Minigames.
Strangely, BB can go under The Office table on occasion. However, his eyes, eyelids, cheeks and hat change color. This version of BB has since been dubbed "Balloon Girl" by the community, and is thought to be simply a hallucination.
BB is one of four animatronics who do not appear in the hallway before entering The Office, with the others being Toy Bonnie, The Puppet, and Chica.
BB's figurine (obtained by beating Night 7's Night of Misfits preset) shows him with a round, red nose that reaches his eyes, instead of his small, triangular nose.
BB is one of only two animatronics to be featured as an unlockable figurine (as opposed to a plushie) that is rewarded to the player after completing a specific Custom Night preset, the other being Toy Bonnie.
When BB is in The Office, while Bonnie, Chica, Toy Freddy, or Freddy is in The Office at the same time, he cannot be seen. However, his laugh can be heard.
Just like the other Toy animatronics, BB was scrapped at the end of Night 6 due to possible malfunctioning.
When BB is seen in cameras and the Left Air Vent Blind Spot, he has black buttons, however in the office he has white buttons. It is unknown why this occurs.
BB is the only animatronic not mentioned by Phone Guy.
BB and The Puppet are the only animatronics who do not have counterparts.
Some members of the community have compared Balloon Boy to the Villager from the Animal Crossing series, specifically his Super Smash Brothers incarnation. Both have a similar appearance (small, large round head with triangular nose, stubby arms) and both attack the player in a more roundabout way, compared to the other characters, that includes the presence of balloons.
The Villager also has a popular alternate interpretation as a psychotic killer underneath a more innocent exterior, to which Balloon Boy has some similar attributes.
