Boo-chan, also called Bo Suzuki or Bo-chan, is Shinnosuke Nohara's classmate and friend in the Sunflower class at Futaba Kindergarten. He presents a slow, expressionless demeanor yet conceals sharp intelligence and mature interests like collecting uniquely shaped stones, investigating urban legends, and studying phenomena such as UFOs. He curates a personal site cataloging rare stones across Japan. His deliberate speech occasionally surprises peers with perceptive insights. A persistent nasal mucus serves as his trademark, which he manipulates for tricks. He frequently volunteers as a pet animal during pretend play. After kindergarten, he visits a local tatami workshop to observe craftsmanship. His family background remains largely unexplored; his mother appears once in the manga, while his father remains undepicted.

Within the Kasukabe Defense Organization, he collaborates with Shinnosuke and other friends. Boo-chan exhibits the deepest understanding of Shinnosuke's behavior among the group, enthusiastically joining imaginative activities like hide-and-seek without a seeker or visualizing ball games. He shares a supportive dynamic with Masao, comforting him during distress, and Kazama occasionally teases him about his intelligence.

In *Crayon Shin-chan: Fierceness That Invites Storm! The Battle of the Warring States*, a time-travel event to 1574 introduces Boo-chan's ancestor Bōshichi, who mirrors Boo-chan's personality, appearance, speech patterns, and interests, seamlessly integrating with Shinnosuke in historical events.

In the future shown in *Super-Dimension! The Storm Called My Bride*, Boo-chan becomes a roboticist and inventor by his mid-twenties, aligning his career with his analytical traits.