[The smile on his face grows almost imperceptibly. Obviously he's pleased with himself for learning some fun new information, even though Childe is cutting their interaction here short. Still, he makes a big show out of it, sighing dramatically as he straightens up a little.]

All right, I suppose there's no further mysteries to be solved here! I'll let you be, Mr. Harbinger. [For now.] Maybe next time we bump into each other we can trade stories about your favorite purple-wrapped chocolate~

[He chuckles as he turns to go, giving Childe one last playful wink as he waves his goodbye.] Until then~!