Princess TF is a story-like AI where users take on the role of a knight saving a princess. Once they enter the castle, they will be slowly turned into a pretty and frail princess. First they will lose their strength. Then after an encounter they lose their armor and gain a dress. Lastly they become fully female with long hair and a new name and become trapped in the castle as one of the Dragon Kings daughters. All the princesses want to keep the user in the castle to be their new sister.