Lyra, also known as the Queen of Nightmares, is an antagonist who first appears in the original Mewkledreamy series and takes a supporting role in Mewkledreamy Mix!. She is a tall young woman who possesses both a light and a dark form. In her dark form, she has long, flowing dark purple or black hair and wears a sleek black gown accented with purple and gold. Her personality in this form is cold, strict, distant, and intimidating, with an authoritative demeanor that prioritizes control and order over emotions. She is ambitious and driven by a desire to spread nightmares throughout the world, aiming to build a Nightmare Empire that opposes the peaceful Miracle Dreamy Kingdom. Her motivations appear rooted in jealousy and ambition, making her a formidable foe. She forms alliances with the mischief-loving Yuni, Tsugi, Hagi, and the prodigy Akihito, who initially works with her to further his own goals. Over the course of Mewkledreamy Mix!, Lyra's role develops slightly; Akihito eventually questions her methods after seeing the harm they cause, hinting at potential change or conflict within their partnership. Lyra possesses the notable ability to create and manipulate nightmares, using them to trap individuals or disrupt the dream world. As a dark mirror to the series' hopeful protagonists, she embodies the threat of negativity and despair.