I would say Death Note and Claymore Death Note has a creepy sense because it scary how someone can become so consumed par their intentions that they become insane O.o
claymore isnt really creepy just alittle gory, and i guess its creepy in that sense. Its plus creepy because its not like most manga because there no comedy and its most all serious but its still good
FMA can be creepy at times... It has a lot of comedy and such, but the homunculi will scare toi shitless! Especially Gluttony and the homunculi Ed and Al accidentally make at the beginning to revive their mother... And now, I shall finish with two citations from this awesome, slightly creepy manga! Can I eat him? -Gluttony WHO ARE toi CALLING SHORT?! -Edward Elric