Mii, a telepathic cat from *DNA Sights 999.9*, appears as a light orange tabby with dark orange stripes, squinted black eyes, a small black nose, and upright ears. The character is occasionally shown with a scar and bandages on its belly.

Originating from Leiji Matsumoto's interconnected "Leijiverse," Mii features notably in *Space Battleship Yamato*, *Galaxy Express 999*, and *Space Pirate Captain Harlock*. Modeled after Matsumoto's own cat who died in 1974, subsequent cats were named Mii-kun II and Mii-kun III. Within *DNA Sights 999.9*, Mii stands as the third evolved lifeform alongside human protagonists Tetsuro Daiba and Rei Yuuki. All three survived a catastrophic meteor strike devastating Earth, possessing latent advanced abilities tied to their DNA.

Mii's telepathy proves critical when the protagonists are captured by the Trader Force regime. The cat enables their escape from Queen Photon's sealed chamber as Daiba and Rei debate trusting Queen Photon or the cosmic entity Mello. Mii's intervention allows their breakout, prompting Mello's arrival to clarify the situation. The trio then faces a pivotal choice: remain on damaged Earth or venture into space.

Personality-wise, Mii exhibits curiosity and loyalty, often displaying comfort and affection toward companions. The cat occasionally acts as a drinking companion for owners and is sometimes depicted alongside another character named Bird. Mii's telepathy and status as an evolved being make it a target for the Trader Forces, who seek to exploit these advanced traits. Its survival of the meteor event and abilities link it thematically to the series' exploration of DNA memory and human evolution.

Mii's design and core characteristics remain consistent across its appearances in Matsumoto's works, maintaining key visual traits and personality elements. Similar cats resembling Mii appear in other titles like *Queen Millennia* and *Queen Emeraldas*, reinforcing its status as a recurring motif within the Leijiverse.