[It's just as well he isn't expecting any sympathies -- from his interactions with Saya, he knows she's not one to talk too much, and never anything that's not straight on point. And in this case, it's good, too, since-- well, since her question really is the most important thing right now. So he exhales, shakily still, his hands forming fists on his sides.]
You have to... change the body. It's a spirit, so you can't kill it, but... it's a fox. So if the body becomes something else, it can't stay there anymore. And then, when it's forced to leave-- then, you trap it.