[WIP] Creating a Monster...want opinions

[failedALIAS]

Make his true face hidden. Put a shade over his face so none of us know how he looks. Make him have huge muscles and large holes in his shirt. make him look business like with a white shirt and decent pants. Make him wielding a knife, a knife that looks bloody and make it look like a knife used in science for cutting open frogs and stuff . I think that will be creepy. Sounds like a good custom story idea I'm looking forward to playing it.

How would that, in any conceivable way, be regarded as creepy? In the proper composition of a frightful monster, one must first take the audience into consideration: Who am I making this for? What are they scared of?
What made the monsters from Amnesia: The Dark Descent scary? It's that they were on the base level, human, but with horrific derangements.