It feels like that ship will happen. Her previous lives never work out with the hero for a reason and I'm betting it's because she can't remember the very first one <_< probably one of them summoned from another world lives that was suppose to be a hero but fell in love with the demon king and he her, but something must have gone horribly wrong? Not sure, but it's an idea from what I'm seeing and the feel of the story so far, but we'll find out as it progresses.
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The demon king was her former lover in the past. He was the hero who returned to her, but ended up seeing her lying dead.
He then became the new demon lord (??) And waited for her soul (???) To reincarnate again.
And no, I dont think that theyll end up together.
Its like the plot from1/2 prince.
Plus, Grahams a bundle of joy uwu
Am I the only one who ships her more with the demon king ?