While he knows of certain past activities done between Zagreus and Megaera, the Furies commonly use their whips on the wicked shades in Tartarus as punishment and not for what Katsuya is trying to imply. He uses a weapon in his daily line of work. Weapons are just common.

Thanatos flips through the pages of the textbook, frowning. The information in the book seems slow to appear, like someone didn't expect a person to investigate too deeply into the specifics.

"Maybe it's in a different book."