It only did so once, and it was not repeated anymore.
Looking out the translucent window (what material was this anyway), Perrot and the others realized that time had passed and night had already descended.
And with the night, came the mobs.
Their hearts clenched, still traumatized by the horrors of the previous night.
Further, it was unlikely that the bell sounded just to tell people of the time. After all, the noise could attract more beasts than intended, so it could only be an alert of enemies.
"Will things be alright? Does that bell indicate that there're… mobs?" Perrot asked the shopkeeper, feeling tentative.
He saw that he was already preparing more and more food. Obviously, he was expecting a lot more customers soon.
"It's indeed an alert that there're mobs in sight," he said, leisurely adding menus on the tables next to them. "Don't worry though, since it was only one bell, it means it's not that urgent."