"Back...?" Terezi stares blindly up at Sam, her brow furrowed and her mouth slightly open. Back? Back to where they took them from when they died? No. No no no. Her brow furrows deeper as that really sinks in. Back to Alternia. For Kurloz, that meant either a life of cruelty and destruction of himself and everything around him... or being snuffed out by paradox time. And for her, that meant going back to a useless life on a meteor that might never reach its destination, spiraling out of control until she was only a shell of her former self. Neither one of those things are anything less than horrifying.

And he's telling her that it's unavoidable?

"...How do you know that going to your world is going to change that?"