In view of a large amount of vermillion obtained and used, it is considered that it has some relationship with eastern Seto Inland Sea, because Tatetsuki Kofun Tumulus which used three kilograms of vermillion is located in Kurashiki City, Okayama Prefecture.
朱を大量に入手し使用している点で、3キロの朱を使用していた岡山県倉敷市の楯築古墳があり、東瀬戸内海との関連が考えられる。