A subordinate of Kirihara's. Traditionally wears a business suit. Despite being an officer, he seems to have little common sense as he infiltrated a gang operation undercover using his real name. He has admitted to finding Kirihara scary. However, Saitō is loyal to Kirihara and protects her from harm, even when he thinks she's frightening. It is revealed in the OVA that Saito has feelings for Kirihara, however soon after verbalizing them his memory along with Kirihara's is erased due to a memory erasing substance accidentally released by Mao.