Siruis is a member of a secret organization that, much like the Hellsing Organization, is aimed towards destroying supernatural creatures. He is actually a werewolf himself, and is shown to be quite a capable monster hunter, wielding a pair of pistols and such. From what is said, he lives in varying lifestyle, depending mostly upon how much ammo he uses to destroy the creatures, and sometimes has to live on bread and water. He is shown to have a crush on Beate after she hugs him and later kisses him in the manga, and is seen blushing when she becomes his companies sponsor.