There had been a time when Kylo Ren would have leapt at the opportunity with an eagerness verging on unseemly- and it isn't as if the offer has no merit. Accepting training from the Sith would give him a level of insight into both paths that would never have been open to him otherwise.

But his experience with Snoke has soured him. Here, beyond the Supreme Leader's reaches, he has been given a new perspective- and his father's words echo in his ears.
  He's using you for your power.
The step closer. The desperation, the grief.
  When he gets what he wants, he'll crush you.

The familiar pain twists in his chest. He will not look, he will not see his father's eyes, he will not feel the love he hungered after for so long in that last, useless touch. Not here. Not now. Not when he is certain the cool, solid mind he pushed up against earlier can sense his weakness. He pushes it down. Drowns it.

"Can you?" he asks, his voice much tighter, now. "At what price?"