Kawamura, a human botanist, joined the Japanese expedition to New Guinea's Baruru Island. While others sought the "Water of Life" for profit, he held no interest in its monetary value. He approached the island with deep respect, befriending local residents and demonstrating genuine concern for their culture and environment. Kawamura actively opposed fellow Japanese explorers to shield the island's sacred areas, a stronghold for Southern Yōkai. This protective stance arose from his dedication to botanical research and an ethical commitment to preserving the island's ecology and culture.

During the Baruru Island events, Kawamura, alongside Nezumi-Otoko and others, was captured by Akamata and the Southern Yōkai. They specifically targeted him due to his Japanese nationality, using him and the other captives as leverage. The Southern Yōkai sought vengeance against Japan for the historical destruction of their sacred land; Kawamura's capture was part of their plan to mutate Kitarō into a giant sea monster (Dai-Kaijū) for an attack on Japan.

Kawamura's background reveals a kind and honest individual. His actions were consistently driven by a commitment to peaceful coexistence, not exploitation. His central role involved advocating for the protection of sacred sites and demonstrating solidarity with the island's inhabitants against destructive external forces.