“I'm sure you will notice yourself growing tired, but whatever makes you most comfortable.” Only because he sounded so inconvenienced by the notion, as if it wasn't entirely his idea to begin with.

Kurama's own reluctance to stick around is entirely that. He knows that Hiei would prefer his space and to do things on his own terms, that much had never changed about him. He's also aware that his presence is somehow related to what started this in the first place, even if his theories on how are educated guesses, at best. The fire apparition may be doing this to himself, but the fox can't help thinking his proximity - and Hiei's jumbled feelings on that matter - only serves to prolong his suffering.

The suggestion to ask Mukuro for a tank is met with momentary silence, the fox not responding right away as he considers before answering. “Perhaps... returning would actually be the most efficient treatment.”