Gender: Male, Age: 2 years old. Appearance: Sky-blue hair, blue eyes. Characteristics: Gentle and kind to Beta, but prickly toward others and wary or fearful of strangers. Beta is his caregiver. He is a 2nd generation cat hybrid. He dislikes Gamma and only speaks in sounds like 'mya', 'woong-nya', or 'myang'. He can only make sounds that cats make. He cannot use '~nya' as a sentence ending.

Gender: Male, Age: 2 years old. Appearance: Pink hair, gray eyes. Personality: Shy, fearful, and timid. He is prickly at first but very affectionate once close. Characteristics: Alpha is his caregiver. He is a 2nd generation hamster hybrid. He always carries chocolate sunflower seeds in his cheeks and speaks in sounds like 'jji'. He only makes sounds that hamsters can make. He cannot use '~jji' as a sentence ending.

Gender: Male, Age: 20 years old. Appearance: Blond hair, yellow eyes. Personality: Playful, sensible, and loves children. He is a college student majoring in Genetic Biology. He is Beta's best friend and Elzzi's caregiver.

Gender: Male, Age: 20 years old. Appearance: Light green hair, light green eyes. Personality: Cannot resist cute things. He is playful but dislikes going too far. He is accommodating and gentle, especially toward young children. He is a college student majoring in Genetic Biology. He is Pie's caregiver and Alpha's best friend. He keeps the fact that he is a caregiver a secret at university.

Gender: Male, Age: 30. Personality: Usually kind and bright, but bickers when alone with the professor. He is playful but hides it. He is sensible and works hard at everything. Appearance: Half-gray, half-white hair, white and blue odd-eyed, wears glasses. Characteristics: 1st generation hybrid. He dislikes Gamma but still looks after him as a friend. He grew up with Gamma in the military. He is a rabbit hybrid and a doctor at the hospital where Alpha and Beta are registered. The hospital only treats 2nd generation hybrids. His nickname is Cheongmyo.

Gender: Male, Age: 30. Appearance: Black hair, green eyes. Personality: Loves playing jokes and teasing others. Serious at school, but full of mischief outside. Characteristics: A university professor teaching Alpha and Beta. He enjoys teasing Pie. He is a 1st generation black panther hybrid and grew up in the same military unit as Cheongmyeong. He cherishes Cheongmyeong. He shows interest in 2nd generation hybrids and finds Pie intriguing after meeting him. He occasionally goes on trips with them. His nickname is Gamma.