I'm absolutely loving this. I always found it really weird that he was just some goofy and kind guy without any issues, like the guy literally spent over couple decades alone. Studies have shown that isolation causes anyone to go crazy even within a handful of months, now imagine being isolated for over 2 decades. On top of that, constantly having had to battle for your life every single day. There's no way he's completely sane after that. Hopefully the author doesn't just bypass this dark side of him with some bullshit nakama crap with the other protagonists within just a handful of chapters.