**SPOILERS**
It’s a mixed bag. The protagonist and one other character escape, and the vampires are stopped. But most of the characters we meet have been turned and/or killed by the end. Definitely not framed as a downer though.
There’s throat biting and we see a wound in a throat, but I don’t remember anything bad enough that I’d consider it mutilation. (Someone check me on this if possible, I’m not especially confident)