breaking Waribashi so quietly
Waribashi （割り箸） are those wooden chopsticks that you need to break apart.
Some people rub Waribashi together when they break them apart, but this is considered as a bad manner. Please use them without doing so. Also, in Japan, "Waru (break apart)" is considered as bad luck. So, when you break Waribashi apart, you might want to do so quietly (=not to do it openly before others' eyes).