Hythlodaeus only laughs in response to the quip, lightly nudging Hades in the ribs.

"Is that so? You do not have enough trust in my ability to embarrass you, my dear Agesandros. I've plenty of other ways to make being my partner unbearable, as you well know."

When Hades locks the door Hythlodaeus does not answer right away, instead spreading his arms and taking a deep breath of the frosty air - theatrically so. Unbeknownst to Hades, it's a way for Hythlodaeus to give himself a little time to think as he ponders over a destination to choose - he doesn't want to come across something that would bring Hades's grim thoughts back.

"Why not simply the park? The trees are quite beautiful under the coat of snow."