It's not a yes...but it's also not a no. But it's something at least as Yua begins to walk away, giving Emet-Selch a simple farewell wave and head on down the beaten path.

"See you around, then!"

She's not worried about his safety or if he can handle himself because after living for thousands of years, one probably knows how to handle surroundings without godlike powers. Or she at least thinks so. Was it giving him too much credit? Maybe. Was she putting people in danger because he can still try to make sure a Rejoining happens? He would have been out of there and given her a blast for good measure.

But if he needs a hand...she'll be there.