By now, it should probably go without saying that Katsuo and Mercer are very close friends who greatly enjoy each other's company and share many skills and interests... up to and including military strategy, from the looks of it.

The two might not be going to war anytime soon, but there are still plenty of nuggets of useful information to be had in terms of one-on-one hand-to-hand combat. Perhaps their next training session or staged brawl will see a few of those put to good use.

Katsuo belongs to GaliosOnyxus, whose birthday I got this for
Art drawn by  MrKermodeBear