Bon Bon is the placeholder name of a background pony. She is an Earth pony that appears in several episodes, and has speaking roles in Call of the Cutie, Green Isn't Your Color, Lesson Zero and The Super Speedy Cider Squeezy 6000. She has a pale cream coat and a navy blue mane with a pink stripe. Her cutie mark shows 3 pieces of wrapped candy. She is very similar to previous-generation ponies similarly named Bon Bon.
Bon Bon shares her appearance with a G1 pony of the same name, including her color scheme and cutie mark. The name comes from "bonbon", French for "candy". Bon Bon is frequently seen next to Heartstrings, which has been explained by a layout artist to be mostly coincidental and based on aesthetic considerations, as far as season one is concerned. Despite only being coincidental in the show, the designer of the Comic Con 2011 promotional poster intentionally placed the two ponies together, Bon Bon is voiced differently in each of her appearances.

I didn't put those in my bag! (Song)

Her new line.