Killing Crestfallen gets me the same amount of souls that killing a drake gets.

Ergo: Crestfallen is a drake from Drake Valley in disguise.

If you think about it, it makes a lot of sense.
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I am snazzier, hot, hot rant. Warily slight as.
Croak rush, OK? Weirder, almighty make out. ::)

He's obviously too crestfallen to do that.

Or, maybe ALL drakes are crestfallen, and since he's disguised as a human it just stands out more. So, all of them are suicidally depressed, but not all of them will kill themselves. Just most.
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I am snazzier, hot, hot rant. Warily slight as.
Croak rush, OK? Weirder, almighty make out. ::)