I was running around in the area where that golden fog door is after beating Ceaseless Discharge. I saw a treasure chest after going through the three taurus demons. After killing that one hanging worm, I ran for the chest, and got annihilated by four of those fucking things. Upon respawning, I somehow and for some stupid reason ran and jumped off the walkway and to my character's death. I lost close to 40,000 souls. I was pretty pissed off.
For the record, this is my first play through on the first game. I played up to NG+3 on the second one. I'm pretty sure I've missed all kinds of shit on this first go around.