I met a schoolmate whose PE world seems uncannily Herobrine-like...

I know that, logically, Herobrine doesn't exist and that people think that there is no such thing through searching through game code etc., but what I saw was true, although it might have to purposely created before I saw it.

Basically, he had full iron gear and iron tools and there was a creeper advancing towards him. He was still afraid (lol) and decided to back up, before falling into a deep 1 block by 1 block hole extending all the way until bedrock. He died, obviously, and later decided to mine beside the hole all the way until bedrock, stumbling upon a very small cave which had no coal or iron etc. in it. Later, he found the place where he mined down and decided to use dirt to make his way back up the hole. However, his path was soon sealed, surprisingly, as he did not block it up himself. Suspecting something amiss, I told him to place a torch on the side of the wall to protect himself from falling gravel. Sure enough, he mined up one block, and gravel fell. The gravel also fell weirdly, as instead of disappearing as would normally happen when gravel hit a torch and broke, it seemed to remained a falling entity, past the torch, but then disappearing when it reached him. Keep in mind that while mining down, he did not hit any gravel whatsoever. Continuing up, more gravel fell in the same way as before. Then, he had to go as he had to go home and his mum had arrived, thus keeping me in suspense.

There.