Lyra Heartstrings

Heartstrings is the name of a unicorn background pony, frequently used by a layout artist for background gags. Her cutie mark is a lyre. Her name is not mentioned in the show, and it first appeared in the accompanying pamphlet of a surprise bag toy released in early November 2011.

Depiction in the series
Heartstrings is frequently used by one of the show's layout artists for background gags, such as bouncing on clouds, jumping around excitedly, drinking from a cup, or slouching on a park bench. She cries when the parasprites eat her pie in Swarm of the Century. A partial list of her appearances is specified in the charts below.

Heartstrings is frequently seen next to Bon Bon. The pairing has been explained by a layout artist to be mostly coincidental and based on aesthetic considerations, as far as season one is concerned. The two are depicted talking in crowd scenes, enjoying a snack, or watching Applejack and Rainbow Dash during the Iron Pony Competition. In Lesson Zero, at one point in the background she physically fights one-on-one against Bon Bon for the possession of Smarty Pants. She later appears in Luna Eclipsed dressed as mummy.

Appearances
Times are approximate and taken from various videos available online.

First party
Heartstrings appears in the November 2011 Surprise Bag toys, being of the same pony kind and bearing the same cutie mark, coat color, mane color, and eye color as the unnamed character on the show. Her pose and mane style are the same as the Twilight Sparkle Surprise Bag toy mold.

Despite only being paired coincidentally with Bon Bon on the show, the designer of the Comic Con 2011 promotional poster led fans to believe he intentionally placed the characters together.

Second party
WeLoveFine.com, which is licensed to sell Hasbro merchandise, carries T-shirts with the fan-made design using the character from the show, with the fan-given name Lyra.

Gallery

 * Heartstrings image gallery

Trivia

 * According to a layout artist on the show, background ponies are nameless, but this pony is labeled "Incidental Unicorn #2" at the studio.
 * The lyre is a common cutie mark in the series, but it also appeared in previous My Little Pony generations, for example on the G3 earth pony Bee Bop.
 * "Heartstrings" refers to deep feelings of love or compassion, commonly used in the phrase "tug at the heartstrings".