Nostalgia
We long for the past, always remembering how good the one that been lost. We so mesmerized with it we forgot to appreciate the present, what we got today.
We always look in the past we never look the future... No we did look the future but we scare of it. The past is locked behind time, interchangeable. We crave for certainly that's why we love it. The future is the opposite, easy to change and any small present action can change it.
The story mostly about something something angel or something something level 6. Then using it as catalyst for something