His backstory: When he was in Japan during ww1 he fled away with his parents to Britain but the plane's engine broke down mid flight‚ only he survived because a strong entient being kept him alive to be the chosen one. His katana is a elemental one so this is the selection

Angry: fire.

Sad: Water

Fear: earth

Emotionless: ice

Pissed off to no return: shadow pure darkness