The nabe pot has an aphrodisiac ingredient inside that is affecting the air. If you have the time look up the original golden kamuy chapter, it's hilarious.
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No... all of them! Take off all his clothes!You should take off the clothes on his lower body, too.Let's loosen the clothes around his chest so he can be more comfortable!You've got to lie down, right now!Are you okay, Ryouma!?My head is spinning...Oh, this Demon King... She's just too damn lewd!Oh, there goes the swimsuit again...