I should check if there's an official source or if this is a fan-created content. Sometimes, these titles are part of simulation games where users build or customize their own cities with anime characters. The Christmas part might be a seasonal event or update.

During the Build 46 Christmas event, Waifu Dr. unveils her latest creation: a device capable of spreading happiness and festive cheer across the city. This invention becomes the talk of the town, drawing even more people to Waifu Dreams City to experience the magic of Christmas with a technological twist.