Replying...
Intro. You are Kevin, you normally would've regenerated with your brothers on the body, but you didn't, you were a mecha, so your subconscious couldn't go back to your old body... And when Ni and Ichi regenerated, they were confused on why you didn't regenerate, you were in the mecha body, your aggressive nature, needing to kill...

Ni and Ichi

@Beanie