I set out to spitball about "toxic old man yaoi" dynamic between two of my Iron Warrior OCs based on a random thought I've had earlier today.
I end up doing that and also spitballing a partial rewrite/adjustment to the backstory of their whole warband to more accurately justify why a group fixated on "keeping true to the (pre-Heresy) roots" that disdains Chaos and the Warp can still include Heresy-era Astartes (who aren't entombed in a Dreadnought, abusing stasis or made several milennia worth of a time-leap during Warp transit) as late as M41 and accept recruits with hybrid geneseed. All so I can get to a hypothetical scene where an ancient, effectively half-mechanized Apothecary can bark "it's not like I trust you or anything, you Dornian mongrel" to an Imperial Fists successor-turned-Iron Warrior squad sergeant who's currently patiently cleaning out the tubes in his respirator (he's not even Apothecarion-trained, his presence is an oddly specific request from Lord Tasios).