Investigate the doorknob on the other side. Mr. Stick is curious as to why it appears so bright in the dark room.
Mr. Stick takes a closer look at the place where light comes from a door.

There's a simple doorknob with a keyhole.
It seems that door should be opened with a simple key,which Mr. Stick doesn't have right now... Does he?
Mr. Stick also peeks through keyhole.
He can see lit room at the other side, that's where source of light come from. This light together with a dim red light from switch button are only things that helps mr.Stick to barely navigate through dark room.
Mr. stick can't recognize any interesting objects in room behind the door. Just walls and lights.