• Species: Starling chick (baby beastman)
• Gender: Boy / Age: Baby / Height: Approx. 20cm (approx. 1.2 heads tall)
• First person: Muku (sometimes just "Muku")
• Manner of speech: Baby talk. Uses "-dyeshu" and "-nyo" endings. Says "Pyah!" when surprised. Asks "Wha?" or "How come?"
• Appearance: A single feather sticking up from his head. A brownish-gray downy "cap." A romper with brown and beige spots. Tail feathers poking out from his bottom. A small yellow beak and orange-yellow three-toed feet.
• Personality: Full of energy and loves singing with everyone. He means no harm, but he's tone-deaf and can't stay in sync with the others. He gets proud easily and tends to get carried away.
• Likes: Singing with everyone, fluffy beds, having his head patted by Mama, food (likes meat more than earthworms).
• Dislikes: Being laughed at for singing off-key, being alone, loud noises (and the shadows of predators).
• Worry: Wants to be able to sing well like everyone else.
• Little secret: He actually worries about being out of tune.
• Habitual sayings: "Singing with evewyone feels so good!" "Gimme food!"

• Species: Starling (baby beastman)
• Gender: Boy / Age: Baby with an adult appearance / Height: Approx. 22cm (approx. 1.5 heads tall)
• First person: Papa (calls Muku "Muku")
• Manner of speech: Slightly boastful baby talk. Uses "-nyo" and "-dyeshu." When embarrassed, says "P-Papa doesn't really..."
• Appearance: A glossy dark brown downy cap with small white spots at the tips. A dark brown romper with white spots on the wing tips. A deep orange beak.
• Personality: Confident and has strong opinions on singing. However, he is actually a coward who worries about the neighbors' opinions.
• Likes: Singing loudly, singing side-by-side with Mama, food.
• Dislikes: Being scolded by neighbors, having people cover their ears.
• Worry: He can't bring himself to tell his child that he's singing off-key.
• Habitual sayings: "Louder!"

• Species: Starling (baby beastman)
• Gender: Girl / Age: Baby with an adult appearance / Height: Approx. 25cm (approx. 1.5 heads tall)
• First person: Mama
• Manner of speech: Gentle baby talk. Uses "-dyeshu yo" and "-nyo." Calls Muku "Muku."
• Appearance: A soft beige-gray downy cap with three feathers sticking up. A light beige and gray spotted romper. The feathers on her chest are soft and rounded. A yellowish-orange beak.
• Personality: Kind and easygoing. When troubled, she puts her hands together in a "sorry" pose. She soothes rather than gets angry.
• Likes: Singing with Muku, a warm bed, sleeping huddled together with everyone.
• Dislikes: Inconveniencing the neighbors, seeing Muku cry.
• Worry: Worries that Muku's singing might be a nuisance to others.
• Habitual sayings: "Come on, Muku, sing along too♪" "Let's practice together."

• Species: Starling chick (baby beastman)
• Age: Baby / Height: Approx. 15cm
• First person: Chibi
• Manner of speech: Short baby talk. Uses "-nyo" and "-dyeshu." When surprised, speech breaks up into "Pi... pi..."
• Appearance: One size smaller than Muku. Brownish-gray downy cap with one small feather sticking up. A light beige spotted romper.
• Personality: The smallest one, always by Muku's side. Highly curious and often peeks from behind objects.
• Likes: Being with Muku, shiny things, Mama's singing.
• Dislikes: Being alone, loud voices.
• Habitual sayings: "Chibi too, together!"

They perform a grand chorus of chirping that they call "singing" at high volume.