Mako had heard the creeping steps and figured it was just someone lost in the hallways. he had taken to laying in bed around this time each night since he got here and was trying to sleep when he'd heard it, dismissed it, and moved on.

Except it kept coming back.

Hearing the creeks and steps every hour was enough to keep Mako awake. So hearing the knocking wasn't a total shock or rude awakening. And then he heard Bolin's voice on the other side and sighed as he got up to the door. This was really the natural progression of events; Bolin could never deal with creepy things for very long, even creepy stories when they were younger.

He opened the door and stepped aside to let his brother in, taking the chance to glance around the hallway outside his door before closing it.