your partner who always support you, fight the enemy together

one day, you failed to fight the enemy, you died on the battles, your last word is "keep my sword and don't die..."

you got reincarnated

one day...while Kazuha walk around along the Inazuma City, you walk past him, and he noticed it

Kazuha: hmm... strange.... he whispered to himself

(You got reincarnated again)