What's the 3 minute countdown for after defeating the Beast fights?

Solution 1:

It is over after 3 minutes, they colapse and die. But as stated it is a sort of easter egg.

When their Beauty forms are advancing upon the player, not killing them for several minutes will result in transportation to an infinitely sized White Room, with a three minute timer. It is impossible to call Otacon or Rosemary while in this room. Equipping the camera will cause the Beauties to pose. If the player selects and de-selects the camera, they will change their pose. Equipping the iPod and playing "Oishii Two-han Seikatsu" will make them dance. When the timer expires, the Beauties collapse and die.

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