Bonnie is a tall animatronic who looks like an anthropomorphic, lavender blue rabbit, with two longs ears, albeit not sufficiently proportioned to his size.
The Silver Eyes
Before Cassidy became Bonnie, she was a young girl who was at Freddy Fazbear's Pizza. On that day, five children were visited by Spring Bonnie, one of the two animatronics (actually William Afton wearing the Spring Bonnie suit).
He lured them into a back room, where he murdered them and hid their bloodied corpses inside soon-to-be-released animatronics. The children's spirits remained trapped in the animatronics.
In 1995, The family restaurant Charlie's father once owned now an incomplete shopping mall has been built in the restaurant's place, but upon further investigation the friends discover the restaurant is still standing, and the mall has been built around it.
After breaking in, Charlotte and her friends explore the abandoned restaurant and find that the animatronic mascot characters - Freddy Fazbear, Bonnie the Bunny and Chica the Chicken, which were built by Charlie's father - have been left behind.
The next day, Charlie and her friends attend the scholarship's launch ceremony at their old school, where Michael's parents give a speech about him. Afterwards, John confesses to Charlie that he remembers seeing a strange person in a yellow Freddy costume at Freddy Fazbear's Pizza on the day of Michael's death, and he now suspects this person was Michael's killer.
That night, Charlie, Jessica, John, and Carlton return to the restaurant, accompanied by their friends Lamar, Marla, and her 11-year-old brother Jason.
They discover the still-functioning control panel which makes the robots move, and Charlie finds a fourth robot - Foxy the Pirate Fox - which cuts her arm with its hook. The next morning, haunted by recent events, Charlie tells John that before moving to Hurricane her father owned another restaurant called Fredbear's Family Diner, which featured two performing robots, yellow versions of Freddy Fazbear and Bonnie the Bunny.
After returning to the pizzeria, William reveals that the robots are possessed by the vengeful ghosts of his victims, and boasts that they will hunt down and kill any intruders. The group tries to hide in a party room, but all four robots corner them.
After Golden Freddy from Fredbear's Family Diner, which Charlie realizes is possessed by Michael's ghost. The Golden Freddy allows them to leave, and Chief Burke arrives to search for the missing Officer Dunn. William attacks in the yellow Bonnie costume, but Charlie activates its spring locks, killing him.
As the robots drag William's corpse away, Chief Burke escorts everyone out of the mall. The friends go their separate ways, and before leaving Hurricane, Charlie visits her father's grave, remembering a happy day she had with him.
Bonnie, along with the other Animatronics returns to help Charlotte and her friends fight William (now Springtrap) and his Twisted Animatronics. The souls in the kids react when the heroes mention Afton.
Five Nights at Freddy's AR: Special Delivery