From Nookipedia, the Animal Crossing wiki
Brewster (マスター, Masutā, Master) is a character who works in The Roost at all hours of the day in the museum. His name is a portmanteau of "brew" and "rooster", or he could be named after Sir David Brewster. He is a quiet, reserved pigeon, specifically, a rock dove with an interest in coffee and, in Animal Crossing: City Folk, an interest in collecting gyroids. He is deep-voiced in all games, like cranky villagers. He sells a random mug of coffee a day at 200 Bells. He prefers the player to drink the coffee as soon as it is given to him or her, and will be shocked if the player responds with "It's got to cool". In Animal Crossing: Wild World, he will admit he owns sugar, but only enough for himself but will be shocked if the player refuses the offer of it.
After talking to him for a while, over a course of a few weeks, he will tell the player his story, which suggests he used to own a coffee shop in the City before moving to the town to open up a small business in the museum, after meeting Blathers.
Brewster's role in Animal Crossing: Wild World remains the same throughout the series. He will serve the player a cup of coffee a day for 200 Bells and be present when other special visitors and villagers are in The Roost. He will also be present when K. K. Slider is performing. After buying coffee for a while, he will offer special drinks which may include pigeon milk. At first, Brewster is reserved towards the player, however, he begins to open up towards the player after he or she have bought coffee for a while.
In Animal Crossing: City Folk, once the player become friends with him, (usually seven cups of coffee), he will offer to store the player's gyroid if the player is holding one while speaking to him. He will store one of each gyroid when spoken to by talking to him from across the bar (not sitting on the stool). He will also offer a shot of pigeon milk, like he did in Wild World. On Valentine's Day, he will offer the player hot chocolate instead of coffee, and will say "Happy Valentine's Day!" instead of the usual "Thanks".
In Animal Crossing: New Leaf, Brewster continues to run the The Roost Café that can be built as a Public Works Project. When the player sits down, he will offer to brew a cup of coffee for them, allowing them to choose the kind of coffee beans, how much sugar, and how much milk they would like. However, beginning with the player's fourth purchase of coffee, they can choose their usual blend of coffee or they can change the blend. In addition, after purchasing three cups of coffee, the pigeon will begin to allow the player to take their coffee to go.
Upon purchasing seven cups of coffee, Brewster will allow the player to work a part-time job behind the counter as a barista, making coffee for the town's special characters and villagers. After completing eight successful orders, the player will be awarded with a piece of furniture from the Café Series.
Brewster appears as a trophy and will sometimes be a spectator on the Smashville stage.
Brewster once again appears as a trophy and sometimes will be a spectator on the Smashville and Town and City stages.
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