Maruki watches the myriad of emotions crossing that boy's face. It felt akin to how he remembered theorizing the way the detective prince projected himself in a favourable light; wondering if there was any part of him that felt too scrutinised to reveal anything else.

And now? Something about the way that Akechi acted was enough to prove to him that no matter what monstrous appendages were attached to him- this was still that human boy.

Which is why Maruki stare catches when he mentions a persona.

How does he know that?

"The Holy grail...that doesn't-" he falls off as he finally leans away from the workbench. How much does he know then? If he lies and the detective catches it, he might end up all alone in this strange place and right now there was no one else here- he is not going to make it like this for long. Azathoth or not he might just end up going crazy-

"I unfortunately have no idea what you are talking about," he answers uselessly. "There’s...so much going on. You know a lot, obviously. "

"Nothing pleasant I could imagine."