What is roseblood, anyway? To me, it is the pain that even the most beautiful creatures must endure. The girl in the song is clearly aesthetically quite attractive. We know this by her lipstick mouth, shining eyes, and her famous hair and smile. The observant narrator knows that something is quite wrong. Nobody else seems to see the slight changes in her hair and smile, or even the slices in her hand. It's a slow decline that no one cares to stop, not even the narrator who admits to being able to wait a million days while the girl's smile goes away altogether...
We all know people like this. I used to go to school with the epitome of one. She was undoubtedly one of the prettiest girls I've ever known. (In fact, she looked a good bit like Hope. Hmm...) She was a good student, an amazing artist, a top-form athlete and horsewoman, and brilliant on the flute. It was so easy to be envious of her and actually be happy when she moved away. The next summer, I was talking to someone who mentioned her. I could picture the perfect girl right away. Her winning smile was vivid in my mind's eye as I heard stories of her manic-depression and multiple suicide attempts. I've talked to her a few times since and she seemed the same and it was almost hard to remember but still so hard to forget that she had a hole where her heart should be.
Maybe Hope relates to this. The seeming perfection that tries to mask inner strife. It can be a lot easier to see yourself in third person, summing up an emotional decay with a short phrase. "She is falling apart." "The girl is crying."
It is funny how things change. The way you see somebody differently, or the way people change so they don't have to fight these demons. It's kind of like a rose wilting, leaving behind a beautiful life to turn into nothing but the memory of the scent of roseblood...

rose might also be the particular colour of the blood to which Hope possibly refers. Maybe the woman in this song is a mythic figure, a luna goddess. This song has layers in which meaning slips beneath the personal to the interpersonal.
Is there bleeding 'by the slices in her hands": a blade, a sickle? Do slices resemble smiles by their cresent shapes? "secrets in her lipstick mouth", lipstick can be black like the colour of night, but what secrets?
"i can wait a million days", is time felt to be so short while she watches the beauty of a silver slice wane? While staring at the moon Hope might have perceived how change comes in cycles, "sometimes i feel dizzy".
If any of these meanings are to be perceptable "Roseblood" needs to be read as the tenor of menses which permits a luna goddess as an extended metaphor.
N.B.: A metaphor consists of a tenor, the subject to which the metaphoric term applies, and a vehicle, the metaphoric term itself.
Only by allowing this metaphor do I have any confidence in this interpretation at all.