A thought for this prompt.

Glass half empty or half full?

Pessimism vs optimism?

Happy go lucky character vs miserable bastard type character?

Bitter sweet memories?

A pessimistic character reflecting on his negativity in life?
Or the reverse; a disillusioned optimistic character who's reflecting back on their life and finding all that went wrong?

I'm feeling some strong AoT Ereri or Merome here, or a war AU?