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.
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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.