While demon light was slowly burning the two black robed figures, Daimon ignored them and focused his attention on the smiling ghoul in front of him.
A smiling ghoul can be considered an endangered species among the undead, they have a really annoying innate ability called "empty bones", it's an ability that allows the ghoul to hide a certain number of things inside its own body.
The number of things was limited to the realm of the ghoul, according to the information secretly kept in the private library of the Revy family, an Arch ranked smiling ghoul could hide up to 10 objects inside his body, hiding them from the eyes and mana sense of others.
Don't let the fact that storage rings exist lessen the importance of the "empty bones" ability, when representatives of races in conflict meet, their storage rings are confiscated as a sign of "goodwill", of course that is an excuse just to prevent someone bringing something that could put others in danger.