Boisterous, Miso
Your mouth is wearing a mask so people won't realize you're the one being so boisterous as you eat your miso. If you cover your mouth with this mask, no one will know you're such a boisterous eater of miso.
Okay, this kanji doesn't actually mean "miso," it just means "boisterous." But you'll pretty much only ever see it in the word for miso, so I figured I'd sneak it in here to prepare you for that… Thank me later.
そ
None
None
You're being boisterous and having your miso outside when suddenly someone shoves soap (そ) in your mouth. "Even your mask can't hide that boisterous miso-eating. Quiet down and wash your mouth out with that soap!" they yell.
Using your boisterous mouth, taste the disgusting soapy soap. The soap bubbles are already filling your mouth and stinging your tongue. This is the punishment for those who eat boisterously.