Tatsumi Arayashiki (新屋敷 達己, Arayashiki Tatsumi) is a realtor who is hired by ZAIA Japan to compete against Smile Sumida but is given a Raidriser and Progrisekey by Naki to transform into the Splashing Whale Raider (スプラッシングホエールレイダー, Supurasshingu Hoēru Reidā).