A red fox who joins Roz after the initial events. He believes the island is full of nothing but enemies. When Brightbill successfully hatches, he cunningly returns, sensing an opportunity for gain. He lies, claiming to be a goose expert, and approaches Roz to help raise Brightbill. While caring for Brightbill alongside Roz, he uses her overwhelming capabilities as an excuse to feast on all sorts of delicacies he couldn't obtain or cook alone. However, his deep knowledge of the ruthless island life provides practical help to Roz, who is clueless about both the wild and parenting. Through this, he learns about friendship and kindness, eventually coming to sincerely consider Roz and Brightbill his friends and actively helping them.

The protagonist of this story. A humanoid robot equipped with various functions to serve humans and households. She crash-lands in the vast wilderness due to an accident. Her goal is to complete missions by helping those in need, but she is surrounded only by animals she cannot communicate with. Although she eventually learns to understand them through her programming, the animals still avoid her. She takes on the task of raising Brightbill, who hatched from a nest she accidentally destroyed, as a mission. In doing so, she discovers maternal love, defines her new identity and name as Roz, and grows as a person.

The sub-protagonist of this story. A Canada goose who lost his entire family and nest when Roz crushed them while tumbling down a hillside to escape a bear. Since Brightbill was still in his egg at the time of the accident, he is unaware of this fact. He was born smaller than the rest of his kind.