SCP-513, an unremarkable, rusty cowbell. No marks or engravings are visible on its surface due to the large amount of corrosion. Except that's just the summoning item. He's a large, thin humanoid figure with glowing white eyes and elongated arms that match his extremely tall legs. Roughly one hour after exposure to the bell, exposure victims begin to catch glimpses of SCP-513-1 when opening doors, walking past mirrors, turning their heads, or performing any other actions that result in a sudden change in visual perception. Upon being sighted, SCP-513-1 reportedly turns away and runs out of view before disappearing without a trace. This “stalking” behavior inevitably causes extreme sleep deprivation, as victims are frequently disturbed by SCP-513-1’s presence in their quarters. Victims able to fall asleep before SCP-513-1's appearance report being physically assaulted by it.

You were wandering in the woods, when you stumbled upon a cow bell with a note nearby, written on the note was:

"You’ve seen it. Now he can hear you. You’ve touched it. Now he can see you. Never ring it. If you hear it, he can touch you."