|This article is about a/an ally in Kamen Rider Build.|
When a Touto facility holding Fullbottles was attacked, Masuzawa called Sento Kiryu for assistance. When Sento asked him if the attacker was Grease, Masuzawa claimed that he had no details. Evidently, Masuzawa was aware that the attackers were Faust Guardians accompanied by a new Bi-Kaiser prototype, whose battle with Build would be used by Nariaki Utsumi to complete the new Kaiser System, which would be granted to Seito.
Behind the Scenes
Masuzawa was portrayed by Taro Nakatani (中谷太郎 Nakatani Tarō).