hassan sensing

"No need to worry. Regardless of being able to see or not, there are no familiars or spells surveying this house. I —"

"— I guarantee that."

The voice of the third person cut in and, at the same time, a black shadow appeared beside Kirei.

The Heroic Spirit that's been accompanying Kirei in spirit form all this time has, at this moment, appeared in front of Tokiomi.

That skinny and tall shadow has a great difference in prana compared to humans. He's 'something inhuman.' A strange one wearing a long black cloak and a white skull-like mask to shield his features.

Yes, he is the first Heroic Spirit to be summoned in the fourth Heaven's Feel, the Servant "Assassin" who made a contract with Kotomine Kirei — Hassan-i Sabbāh.

"No matter what tricks they play, they cannot hide it from my eyes, the eyes of the Heroic Spirit of Subterfuge, Hassan. My Master, Kirei, does not have any aura of being followed by an enemy around him... you can relax."

As if understanding Tokiomi's position was higher than that of his own master Kotomine Kirei, Assassin politely reported with a bow.

- Fate/Zero, Act 1, Part 3