Lyra Heartstrings is a mare that has some strange habits. She sits upright on benches, she plays a lyre even though such an instrument is more suited to Griffons and Minotaurs, She doesn't recoil from meat, raw or cooked and has admitted to eating it in the past. She speaks about the ancient humans of legend as if she knew one personally.

She also never speaks about her past, and her friendship with Bon Bon has a single rule:

Never go into her room.

When that rule is broken, it starts a chain of events that reveals the mysterious past of Lyra Heartstrings, told by a group of the most unlikely friends.