VALTIEL

  Valtiel is the strange creature that appears in Silent Hill 3. The word Valtiel comes from "valet" which means attendant. Its purpose is to make sure that Heather is ressurrected when she dies and make sure she would birth the God. Valtiel is a saintly being corresponding to an angel that watches over Heather. In many places you can see Valtiel turning valves, it means two things: one is that it represents the cycle of rebirth. It also means that God can be reborn any number of times. And secondly, you see Valtiel turn the valves when the worlds shift, so it represents a change in something (usually the "real" world turning into the nightmarish alternate world) thus making Valtiel a guide into the otherworld.

  Reference to Silent Hill
In the school otherworld you can see several body-shaped figures. The clothes that the figures are wrapped in are actually the ceremonial robes of the town's religion. The robe is modelled after an angel from Silent Hill's traditions, thus it's a reference to Valtiel.

  Reference to Silent Hill 2
I bet everyone has noticed the similiarity between Valtiel and Pyramid Head. They look alike, in fact, if you removed Pyramid Head's helmet, you would get a being similiar to Valtiel. Also, Pyramid Head's outfit was modelled after Valtiel's and this is why those two look a lot alike. But keep in mind that they are not the same creatures.

Be sure to also read the theory about Xuchilbara