[Koumei leaned up against a wall nearby and watched with interest, rolling around the little bead between his fingers while Mutsu tried to make sense of this.]

I would suggest a bored Kogitsunemaru, but this seems a little elaborate for him.

...and particular. There are many more interesting munitions besides simple beads.

[He held the bead out for Mutsu, if he wanted to take it.]

What are your thoughts?