Kunimatsu Sakiyama (born 1940) was a homeless Japanese man who lived in Kabukicho, Tokyo during the 1980s. On 12 December 1988, he and four other homeless men were confronted at Public Park 3 by former yakuza Kazuma Kiryu, who was investigating Tachibana Real Estate, and they agreed to tell Kiryu about Tachibana Real Estate in exchange for drinks. He warned Kiryu that, when he investigated Tachibana Real Estate in the Golden Gai neighborhood, the locals would grow uneasy at the site of a yakuza.