Lost university {L,U}

Just an innocent girl that was tainted because of her family, she secretly learned something dangerous and hide it herself, a girl who used to be happy and cheerful was already gone.

She only have her 2 friend by her side and they discover a mysterious School, a lot of secret and history is hidden.

Can she and her 2 friends can survive in this mysterious and creepy school?

Because once you get in, you can't leave anymore...