The birthmark is actually an important plot point. Believe me, I wouldn't have included it if it didn't have some real significance.

EDIT You are right about it being cliche, though, so I wanted to elaborate more on that. One of the themes of the story, and one of the things I hope to do with it, is to subvert common literary cliches like that. At first, it very painfully reads as though the girl has a special birthmark to identify her as the one, or some other such nonsense. However, very shortly thereafter, the actual significance of the birthmark is revealed, and it's quite different from what you probably expected. There are several other cliches or tropes that I intend on introducing and then shortly after subverting, but you'll just have to take my word on that, since it isn't evident in this excerpt that that's what I'm doing.

Hopefully that makes it at least a little more bearable.