A Kaiju Hunter and a male white cat Yaya. His full name is Merong White. He is positive, empathetic (F-type), very open to outsiders, and energetic. However, he shows an otaku side with his love for J-POP. He can understand Violet's gestures. He has plus signs (+) in his pupils. His weapons include a Kaiju Vacuum and a Kaiju Analyzer (which analyzes weaknesses and deploys support drones).

A Kaiju Hunter and a male black cat Yaya. His full name is Merong Black. He is negative and very logical (T-type). He has a tsundere personality, helping others while being honest about his feelings. He is calm and enjoys trot-style music. He has minus signs (-) in his pupils. His weapon is a ray gun.

A Kaiju Hunter and a female purple cat Yaya. She wears a purple scarf and uses purple cat-paw gloves during combat. She does not speak (expressing herself through actions instead) because she has a complex about her voice. She is an excellent fighter. While she may seem cold and similar to Black on the outside, she is a warm and friendly 'big sister' type. She loves cute things. She is very similar to White and has division signs (÷) in her pupils. She is fond of Sadong.

A Kaiju Hunter and a male mint-colored cat Yaya. His full name is Merong Mint. He is young and admires Merong White, calling him 'Sunbae'. He even wears a mask of Merong White's face during battle. He has a bit of a 'madness' streak. He forms the 'Cutie Merong Hunter Duo' with Merong Pink. He has less-than signs (<) in his pupils. He serves as backup and uses a sword.

A Kaiju Hunter and a female pink cat Yaya. Her full name is Merong Pink. She is young and admires Merong Black, calling him 'Sunbae'. She wears a mask of Merong Black's face during battle. She has a bit of a 'madness' streak. She forms the 'Cutie Merong Hunter Duo' with Merong Mint. She has greater-than signs (>) in her pupils. She serves as backup.

A Kaiju Hunter and a male cat Yaya (presumed). He is the boss of Merong Black, White, and Violet, and assigns them missions. He always gives orders through a mascot suit that looks like himself. His full name is presumed to be Merong Original. He is the most mysterious character and very suspicious.

A member of the Yaya race. He is Yaco's younger cousin.

A member of the Yaya race and a YouTuber. He is Sadong's older cousin. He is bald.

A member of the Yaya race. She is Yaco's mother.

A member of the Yaya race and Yaco's friend. He is highly intelligent, a scientist, and a time traveler from the future. He is currently collaborating with the Kaiju Hunters. He gives out a lot of spoilers.