China, much like Winry has a deep distrust and dislike for Shibusen. Because of that the two of them have agreed to form a small group to 'watch' over Shibusen and try and figure out all they have kept hidden from their recruits.

Despite herself Winry likes China. He's serious, intelligent, and listens. He brought her Rock's armor to experiment with, and is curious about her line of work. That he also practices medicine, and has over four-thousand years of experience makes her respect him deeply.

-Excluding cast mates, the only person she really trusts in Death City.
-Has started learning medicine from him.
-Formed group to monitor Shibusen with