Oh gods, his cousin really thinks he hasn't figured it out? It's actually precious. Adorable! Hermes has the sudden impulse to pinch Zagreus' cheeks. But he restrains himself. Instead, his usual blithe smile breaks for a moment with genuine fondness, his eyes flashing with amused affection before he averts them to look at the sky instead, putting a hand on his hip.

"No need for pretensions here, Coz. I've heard from a bird or two it's not the mountain you're after. And I assure you, your secret is safe with me, as is hers."

Hermes' usual opaque smile is back on when he looks to Zagreus again. He's very good at seeming perfectly affable while giving nothing away. "I just thought that you might like some more time to see the surface." And maybe see Persephone. Hermes wouldn't blame Zagreus for using all his extra time to run to his mother and hear all she has to say.