Mī-kun is a tabby cat character from Leiji Matsumoto's works, directly modeled after the creator's own cat who died in 1974. This personal bond deeply informs the character's core inspiration. Physically, Mī-kun possesses light orange fur covered with dark orange stripes. Key features include piercing squinted black eyes, a small black nose, and straight-up ears. The design sometimes incorporates a scar and bandages on the belly.

In personality, Mī-kun embodies feline curiosity and shows fierce loyalty when met with care and affection. The cat weaves comfortable bonds with humans and occasionally serves as a drinking companion. Mī-kun is frequently depicted alongside the recurring character Bird.

The OVA special "Torajima no Miime" centers on Mī-kun, adapting Matsumoto's 1978 manga. It follows the cat's integration into a new adopted family. Key events involve a conflict with a dangerous neighborhood stray and a later story where an elderly family cat returns after a decade feral for a final reunion, portraying Mī-kun's place within family and neighborhood dynamics.

Beyond this special, Mī-kun appears throughout Matsumoto's interconnected "Leijiverse," including "Space Battleship Yamato," "Galaxy Express 999," and "Space Pirate Captain Harlock." "Galaxy Express 999" episode 37 presents a bold reimagining: Mī-kun as the spirit of a deceased pet cat manifesting as a human woman. Visually similar feline characters, bearing Mī-kun's distinctive traits, also appear in narratives like "Queen Millennia" and "Queen Emeraldas."

The character's background remains tethered to Matsumoto's personal history, with the creator's subsequent cats named Mī-kun II and Mī-kun III, perpetuating the original pet's legacy.