Meow, whose real name is Mymyamo, is a companion of the alien hunter Dandy and a resident of the spaceship Aloha Oe. He is an alien from the planet Betelgeuse, which explains his feline-like appearance, though he is not a genetically advanced cat as one might initially assume. His nickname was given to him by Dandy and the robot QT, who find his true name impossible to pronounce. Physically, he resembles a small, upright cat with large yellow eyes and tan fur marked with spots of brown or grey. His typical attire consists of a red cap, a light green sarong, a brown satchel worn around his waist, and a pair of orange crocs.

Meow possesses a personality defined by extreme laziness and a carefree attitude. He spends the majority of his time on the Aloha Oe playing video games, reading manga, and using his smartphone. He is deeply addicted to social media, where he posts updates and photographs under the handle @Myau_Space☆Hunter. This habit, while primarily a leisure activity, serves as his main method for gathering information on the locations of rare aliens, contributing to the crew's hunting missions with varying degrees of success. Despite his often useless behavior and freeloading tendencies, Meow genuinely believes he is a crucial and helpful component of the crew, a delusion that frequently causes friction with Dandy.

His motivations are largely self-serving and simple, revolving around eating, relaxation, and entertainment. He has a large appetite and considers himself a connoisseur of ramen, and he enjoys snacking on items like potato chips and canned peach nectar. His hygiene is notably poor; he dislikes water and rarely bathes, preferring to lick himself clean, a habit that leaves him smelling like fish and disgusts his crewmates. Meow also shares Dandy's enthusiasm for the restaurant chain Boobies, and he has a perverted side, as he was first discovered by Dandy while taking inappropriate photographs of the waitresses. He also owns a dakimakura, or hug pillow.

In the story, Meow serves as one of the primary members of Dandy's crew. His role often involves providing commentary on the crew's dire situations, using his social media to track leads, and occasionally using his knowledge of his home planet. His key relationship is with Dandy, which is vitriolic and based on mutual annoyance. Dandy frequently views Meow as a useless freeloader and does not hesitate to abandon him in dangerous situations. However, underlying this frustration is a grudging sense of camaraderie, as Dandy has risked himself to save Meow on multiple occasions. Their dynamic becomes friendlier as the series progresses. Meow also has a relationship with his large family on Betelgeuse. As the eldest son, he was expected to take over the family's metalworking business, a future he rejected to travel space. While his father was initially disappointed, he eventually came to support his son's choices. Meow also has a known crush from his past, a Betelgeusian girl named Katie, which ended poorly. Despite his claims of disliking her, he was devastated by the death of a creature named Pup and revealed he had secretly wished to be her friend.

Meow exhibits little in the way of notable combat or technical abilities, though he is depicted as a potentially talented artist based on old schoolwork. His primary skills are his savvy with social media and, more significantly, his apparent acceptance of the bizarre multiverse they inhabit. In the second season premiere, the crew discovers the nature of reality, pulling strings in Dandy's hair that transport them to alternate dimensions. This results in numerous alternate versions of Meow appearing on the ship, highlighting his existence as a constant across multiple universes.