THere are 2 things I hate in Demons souls.
1º Maneater , the boss isn't a pain in the ass because it is hard, it is hard because you have the first maneater that once he pounce off the bridge ( 90% of the time) he flying around for 1 minute rarely coming down at all and if he does, it is to walk out of the bridge and fly some more, then the second maneater comes and you have run around the middle flame thing with 2 maneaters almost full hp.
2º valley of defilement ( worst level design of any souls game ) almost every 4 or 5 meter you have the camera beeing pushed by something ( moving your character in a diferente direction instantly ) or when fighting, it places it self behind wood planks or any kind of environmental mesh and therefor you can't see S*** I swear I got traumatized by this world, when I got to blightown in dark souls, I thought it was going to be valley of defilement all over again ( good god it wasn't )
And those 2 things are the reason I kinda prefer Dark Souls