kucha-kucha
The annoying sound of chewing with an open mouth — smacking lips, chewing gum loudly, considered bad manners in any culture.
💡Chewing gum loudly — 'Stop chewing kucha-kucha!'
ガムをくちゃくちゃ噛まないで。
Don't chew gum kucha-kucha.
It's bad manners to eat ___ with your mouth open.
○○食べるのは行儀が悪い。