Oh my god, this is dark and beautiful and brilliant in so many ways - the visceral horror of the labs, Celes's complicated relationship with humanity and inhumanity in all their varied definitions (and the way she empathizes more with the Espers than human life!), Kefka's slow deterioration and the lingering traces of who he used to be, the way that both of them have been changed and are changing and can't stop it... Seriously, this is perfect. And those last two lines - well, the whole thing, really - are like a kick in the heart.