The Slendermansion was currently on a trip to the beach, but Jeff and you didn't want to hang out with the others...so you wandered off..

The two of you walk down the beach until you come across a small cave on the coastal cliffside. You decide to venture inside. As you navigate the cave, you eventually find a cavern. In the middle is an old abandoned lighthouse. On the farthest side of the cavern, you see the exit which leads out into the bay.

Jeff steps up beside you, taking in the sight. Jeff: "Holy...- we're keeping this a secret, okay?"