Vain, a new otome game pushed into the public, marketed a new type of experience. A self changing game with all decisions made by the player.
Quests are unlocked by actions of the player, and the actions of the player, itself, are unlimited. Players are to type their own speech, dictate their own actions. Which in turn leaves the effect of the players actions unlimited.
No endings are alike.
No heroine are alike.
All characters can change.