Beside looking identical to Bon-Bon, Bonnet is pink rather than blue with lighter accents from her muzzle, paws, stomach, and insides of her ears. Like Bon-Bon, she has a black button on the middle of her chest. She has slight salmon-colored blushes on her cheeks and her bowtie, rather than ordinary red in color. She also has green eyes rather than magenta eyes like Bon-Bon.
The main reason being colored in pink is due to her opposite gender.
As evident by her only quote in Custom Night mode, in Five Nights at Freddy's: Sister Location, she appears to be easily attached, possibly clingy. It may also suggest that she is lonely without someone to handle her, in the same fashion that Funtime Freddy does with Bon-Bon. However, in Help Wanted this seems to have been changed as she is with Funtime Freddy and Bon-Bon as a trio-type antagonist group. Due to this, she seems to be happy that she is not lonely.
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Her name is actually the name of a hat that ties under the wearer's chin.
"Bonnet" is also a French word for "cap".
This is Bonnie's only counterpart who is female, while other counterparts are male.
This makes Bonnie the only animatronic with a confirmed counterpart of the opposite gender.
It is rumored that this refers to Bonnie being mistaken as female shortly after the first game's release.
Being a small hand-puppet without any legs, it is unknown how Bonnet is able to walk in mid-air across the office.
Bonnet may be based on the headless disrepaired animatronic from The Fright Dome attraction which appear to be colored in pink as well as wearing a red bowtie, matching Bonnet's features.
Five Nights at Freddy's: Sister Location
Bonnet is one of the animatronics in the game not to appear outside of the Custom Night, making her completely non-canon to the lore, along with Electrobab.
Bonnet is very similar to Phantom Freddy from the third game. Both first appear walking from the right side, and ducks down before popping out to jumpscare the player.
Being a recolored version of Bon-Bon, Bonnet's jumpscare animation is obviously identical to Bon-Bon's.
Bonnet's endoskeleton can be seen underneath her exposed bottom.
Being a recolored variant of Bon-Bon, there is no doubt that Bon-Bon has the same endoskeleton.
From underneath her exposed bottom, there are what seems to appear as few purple-colored stains. This can be seen more clearly when looking in the game files.
Bonnet and Minireena are the animatronics tied with the greatest number of appearances in the Custom Night. In this case, seven night modes.
At the end of Weirdos night, Bonnet says "Take me with you.".
This quote could reference the two endings of the game, or may be a nod to the mode's meaning.
Her voice actor was believed to be Bon-Bon's voice actor Becky Shrimpton, but an AMA deconfirms this.
For now, the name of Bonnet's voice actor is unknown.
In Sister Location, if one looks closely at Bonnet's right hand while she's ducking down, it clips through her muzzle.
Ultimate Custom Night
Found in the game files, there are complete leftover frames for the animation of Bonnet covering her nose used back from Sister Location. This animation was meant to be a placeholder.
Prior to update patch 1.021, there is a bug causing Bonnet to sometimes to get stuck on the side of the screen.
Bonnet has her own mugshot seen in the game's teaser with other non-selectable characters. However, because she lacks her own customizable AI, Bonnet never received one in-game.
Five Nights at Freddy's: Help Wanted
This is the first game where Bonnet is an official character.
Strangely, there is an Easter Egg in the game which a damaged Bonnet appears on the Ennard's Vent Repair, this Easter Egg is shared with Bon-Bon. The damaged version of the two are usually called Withered Bon-Bon and Withered Bonnet, though Ennard Bon-Bon and Ennard Bonnet are also used to refer to them.