No716,No894,No181,No563 are the life forms created by experiment of Steroid-Lostnumbers Laboratory,in a certain world.
Steroid-Lostnumbers Laboratory sent them to there to collect information of real world.
They have settled in a certain deserted building, and have communicated with human by music.
Every night,weird music was heard from the building where no one is sure to live...
So,people began to call the building [Freak's Mansion]....