Its density seems to come and go. No matter how thin it gets, I don't think it's going away any time soon.

[which means he's of the same mind as her: if the things come with it, they probably retreat with it, and he can focus on the other aspect that seems to plague whoever's exposed to the noxious fume]

I don't have a death wish [probably], but we need more information before we can move forward properly. If there's a key to resisting its hold in order to get out of here, we need to find it.

[a glance back at her, and there's something imploring about mismatched eyes:] Will you help or not?