Series got cancelled, we're lucky the author managed to publish an ending and especially that they gave us a happy one where they'll be together. There's other examples of authors reacting badly to a cancellation such as the Gal Cleaning author who instead of quickly wrapping up his series...
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During the montage I don’t think she was also off elsewhere sleeping with other people like he’s shown to be or the author would have shown it, I think the more plausible explanation is the latter part of the montage happened because she began taking herself out at the start of the day as CH...
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Agreed, I don’t buy into the “she got out of the loops before him” theory, I think she just started taking herself out the moment the day reset and he gave up as there literally was no way to save her anymore as she was dead by the time he would open his eyes
My belief of what happened with the loops is that she gave up
We see in the early montage they are having sex at the school, outdoors etc, so they were trying basically every sexual thing they could think of but eventually she got tired of it and gave up only wanting to die, we see in images...