Fort Francis is a large castle found in the Bitlands, a realm in Super Paper Mario. Fort Francis only appears in Chapter 3-4 of Super Paper Mario. It is occupied by several Cat-themed robots controlled by Francis, a geeky lizard that captured Tippi during the events of the game.
The castle is patrolled by robotic cat maids that cater to their lord and master, Francis. The castle has a thorough security system that includes cat maids and a kitty laser door that requires two keys to access. The keys are located in the double towers at the opposite ends of the castle. Under the castle is a cage that has the pixl Carrie who, as the name suggests, carries Mario over certain obstacles.
The cat maids have two different special cat maids that specifically guard the two towers of the fort. These guards are used to quiz the entree and then ask for a passcode. If the passcode or quiz is answered wrong, the entree is sent into the basement. There are maids that launch little maids that then explode in a couple seconds. Francis uses these explosives during his fight with Mario and his party. Giant cat maids are found inside of the two towers of Fort Francis.
Chapter 3-4: The Battle of Fort Francis
Mario, Princess Peach, and Bowser finally reach Fort Francis where they are one step closer to rescuing Tippi. They make it inside and finally can see behind a door that Francis is talking pictures of Peach. Eventually, the heroes come across the Pixl Carrie whose ability is needed to get to one of the keys in the castle. After getting both keys, the heroes are finally able to make it inside Francis' room. However, the door will only allow Francis himself or "hot babes." Peach is able to get inside and, after destroying Francis' Swoon.exe program, gets into a fight with. The heroes are able to beat Francis and free Tippi. Tippi is happy that Mario and the others went out their way to rescue her and a Pure Heart soon appears before them. The heroes finally have four Pure Hearts in their possession and are halfway there to saving all worlds.
References to other Paper Mario characters
Throughout the fort, Mario finds many posters, figurines, plush toys, and other information on other Paper Mario-themed characters. Characters such as Pennington, Punita, Princess Peach, and Yoshis among others appear in this way. By looking at the list of "Wanted Things" that Francis has, one can see many references to Mario memorabilia that doesn't actually exist but does in this universe. Such Items include a Cyborg Wart action figure, Grodus Chronicles comics, a Ms. Mowz figure with "Real Smooching Action", and many more.