Zagreus' essence is prone to prodding back, and not very clean about it, all thorns and tar and things you can't get off your skin without losing a layer or breaking out the turpentine. He doesn't think much of the contact either; it's cloying and clove-y in ways meant to teach things like him to be more careful what they try to ingest; not something he'd encountered before, and it makes him defensive. Maybe it's the mental equivalent of drooling that has his eponymous rhyme on the tip of his tongue, but he refuses to spit that out as an answer to Gabriel's questions.

Not that he has a great answer lined up anyway. "A debatably mythical harbinger. A consequence. The inevitable destruction of Time." And something someone else made and lost control of, and a scary story to keep time-sensitives' feet under the covers, and a metaphysical infection. Etc. "There's a lot of luggage."