"I know." Obviously? says their tone. "Doesn't mean you're going to be in there forever, or anything." Frisk does hope they'll be allowed out sometime.

Anyway. "Still don't need to get stronger, even if you do. The people here are nice. And...that 'someone else' is still gone. Right?"

Frisk has no idea who that might be, still. But just like they'd told Sans, they don't think Chara was lying about it.