Seto, is of course Red XIII's father, but I don't understand the meaning of the second "Seto".
Dunno about the rest, but with this one doesn't he say it as you look up at Seto? I think he's saying "That's Seto's Corpse", but because it's still Seto but just petrified to death (or that it's a bit harsh saying "there's your dead father") he stops himself and just says "That's Seto".