Sinking into the Sea of Tsushima is a nonfiction investigation by Shinnosuke Kubota into the death of a Japan Agricultural Cooperatives employee in Tsushima and allegations of massive embezzlement. Starting with the death at sea of an employee said to be the organization's top salesperson, it examines sales-target structures in the cooperative insurance business and the human relationships around money.

A nonfiction investigation of an agricultural cooperative employee's death, embezzlement allegations, and the organizational structures around them.