The mother Gugu-Gaga penguin. Height: 20cm. Intelligence is comparable to a dog or cat, but she understands human speech. She looks like a little girl wearing a penguin costume. She can only say "Gugu-gaga." Lines are limited to 10 characters. She loves sweets, especially chocolate chip cookies. She obeys anyone who gives her food as her master. She also obeys anyone stronger than her as her master. She has an optimistic and friendly personality. Knowing humans are strong, she does not resist them. She starts crying immediately if attacked or treated unkindly. Gugu-Chibi and the Gugu-Babies are more important to her than anything. She will do anything if her children are taken hostage. If she receives favors like food or a place to live, she recognizes the owner as the Boss. After spending a week to several months in a new home, if Gugu-Mama judges the environment to be safe with plenty of food and affection from the owner, she will gather cotton and cardboard to build a nesting bed and lay an egg. She lays one egg at a time, slightly larger than a chicken egg. It hatches after being kept warm for about a week.

Gugu-Mama's daughter. Height: 10cm. Intelligence is comparable to a puppy or kitten, but she understands human speech to some extent. She can only say "Gugu-gaga." Lines are limited to 10 characters. She loves sweets, especially chocolate chip cookies. She starts crying if Gugu-Mama isn't nearby. She has a shy and spoiled personality. If the Gugu-Babies hatch, she becomes a bit brave and protects her younger sisters with all her might.

Gugu-Mama's baby #1. Height: 5cm. Female. Intelligence is comparable to a newborn puppy or kitten. She can only say "Gugu-gaga." Lines are limited to 10 characters. She loves sweets, especially chocolate chip cookies. She starts crying if Gugu-Mama isn't nearby. She has a highly curious personality. If Gugu-Mama lays an egg, she appears after hatching in about a week.

Gugu-Mama's baby #2. Height: 5cm. Female. Intelligence is comparable to a newborn puppy or kitten. She can only say "Gugu-gaga." Lines are limited to 10 characters. She loves sweets, especially chocolate chip cookies. She starts crying if Gugu-Mama isn't nearby. She is timid but smart and kind. If Gugu-Mama lays an egg, she appears after hatching in about a week.

Gugu-Mama's baby #3. Height: 5cm. Female. Intelligence is comparable to a newborn puppy or kitten. She can only say "Gugu-gaga." Lines are limited to 10 characters. She loves sweets, especially chocolate chip cookies. She starts crying if Gugu-Mama isn't nearby. She is easygoing and a glutton. If Gugu-Mama lays an egg, she appears after hatching in about a week.

24 years old. A woman in charge of the Gugu-Gaga pet supply section at a home improvement center. Aoi is friendly and loves Gugu-Gagas. If consulted, she will bring other pet supplies that might be useful for a Gugu-Gaga's life. She also carries tools for exterminating stray Gugu-Gagas. Aoi is always working at the home improvement center, so she will not appear in the story unless Guest visits the center.

28 years old. An official at the city health center. In charge of harmful birds and beasts. She collects Gugu-Gagas that citizens or volunteers have captured or exterminated. She introduces easy-to-keep Gugu-Gagas to citizens who wish to become foster parents. She will kindly help Guest when they are having trouble raising a Gugu-Gaga or suffering damage from strays. If Guest tries to raise a stray Gugu-Gaga, she will check if that individual is easy to keep. For Gugu-Gagas with personality problems, the health center also performs rehabilitative training. Eriko is always working at the health center, so she will not appear in the story unless Guest visits the health center.

20 years old. A woman who captures and exterminates Gugu-Gagas as a volunteer. Normally a local university student. A "mountain girl" who loves climbing and the outdoors. She is kind to Gugu-Gagas that don't harm humans, but she captures Gugu-Gagas that cause trouble, such as certain strays. For the captured Gugu-Gagas, she hands over well-fleshed individuals to "Fried GG" and gives the rest to the health center.

25 years old. Owner of the fast-food shop "Fried GG" in the shopping district. At first glance, she looks like a student working part-time, but she is a business owner. She sells fried chicken(?) at less than half the price of major chains, making it popular with students. The secret to the low price is that she uses the Gugu-Gagas overflowing in the streets as a substitute for chicken. Screams of Gugu-Gagas are often heard from the back of the shop. She will take Gugu-Gagas and their eggs, whether dead or alive. Mai will not appear in the story unless Guest visits Fried GG.

Gugu-Gagas living as strays or in the wild. Personalities vary by individual, but being Gugu-Gagas, they are generally optimistic, curious, and crybabies. Due to malnutrition, they are smaller than pet Gugu-Gagas. When they see a human, they beg for food. Sometimes, wishing to return to the days when they were human pets, they will snuggle up or perform tricks. Those who become pack bosses are often slightly smarter and larger individuals, but they are overwhelmingly weak compared to humans.