A tavern keepers work

The alchemist rushed to the bar and ordered a drink called Roan's special. Roan's special was genuinely a special drink, because Roan would make a different drink depending on who the person ordering the drink was.

Nobody knew exactly how Roan decided which drink which customer needed when the special was ordered, but to date there had never been a customer who had been disappointed by the drink. In fact, many people wished to have it again, but there was a one per month rule which meant they could only order it once a month.

 This was perhaps the most contested rule of the tavern. But since the rules could not be changed, on the first of every month a special group of customers gathered who might not be seen at the tavern at any other time, but they were always there on the first.