In space, no one can hear you scream (with rage) (except for the whole ship)
One day, Hokuto Umeda thinks, Akiha is going to get killed in the face by Klingons, and Umeda is not going to stop it, because the Captain will well and truly deserve it. He will, in fact, laugh. He will say, I told you so, even though Akiha will be too dead to hear it, as clearly Akiha is too stupid to live, because Umeda has told him so, on numerous occasions, and nothing feels quite as good as vindication. There may even be celebrating, because his headache will finally have a chance to abate, and as First Officer he will be promoted to Acting Captain and will be able to run the damn starship the way the universe intended for it to be run.
Umeda ignores the part where this is sadly all filthy rotten and above all delusional lies, because he is quite good at self-delusion, and he would much rather tell himself these comforting lies that make him feel better about how much he wants to strangle Akiha on a daily basis than deal with the sad, pathetic truth that he would put a stop to Akiha's inevitable death-by-Klingon, assuming Akiha didn't do it himself first by being irritatingly and incomprehensibly competent, or he would die trying.
Umeda is allergic to caring. Akiha has ruined his whole fucking life, he is sure of it.
Facts about Umeda:
* Umeda is the First Officer because Akiha wheedled him into it. There was emotional and possibly even literal blackmail involved. He doesn't like to talk about it, mostly because it would mean admitting that the real reason he agreed was because he thought Akiha would probably get his stupid head bashed in if he took an inferior First Officer.
* They did have a Science Officer. Once. Umeda fired him for incompetence, and Akiha rolled with it, because that's what he does. He's nice to the peons, but he doesn't stop Umeda terrorising them as he will. The upshot of all this is that Umeda now has two jobs. But that's okay, because both appeal to his talents: yelling at Akiha, and bossing around minions. Also occasionally killing stuff, which is good for his anger management.
* Umeda was on the medical track before he switched into the command track. He might have fired their CMO by now, but he mostly actually likes Ebi, and she's not that incompetent by people-who-are-not-Umeda standards (even though he persists on pointing out minor errors every time he has to go to medbay - it wouldn't do to let her get too comfortable). Then there's the minor detail that Akiha might not actually let Umeda fire her, because they used to be a couple and Akiha somehow manages to achieve amiable exes, which shouldn't even be possible. Umeda is less bitter about all of this than people (Io) accuse him of being.
Not to mention that having three jobs would be a bit ridiculous, even though Umeda is sure he could totally run a whole starship if he wanted to. Ebi might also have pointed out to him that CMO is a full time job and he couldn't do it at the same time as being First Officer, because he'd have to spend most of his time in the medbay, not chasing after Captain Akiha. Umeda had briefly lit up at that before she reminded him how much time Akiha spent in medbay with various ridiculous injuries, and how annoyingly whiny he was when he was sick or hurt. She then added that of course, Akiha might alternatively end up in the morgue without Umeda as back up, so there was that option?
Umeda let her keep her stupid job, jesus.
* There is a rumour amongst some crewmates that Umeda is secretly a Vulcan or something, because he is scary efficient. Okay, mostly he's scary efficient at yelling at the Captain and ordering around science peons, but still. And he's scary smart, too! People with actual sense make the valid point that a) he doesn't even look like a Vulcan and b) that aside, he's angry, like, all the time. Which they are pretty sure is frowned upon on Vulcan. What with it being an emotion and all. Umeda is pretty emotional.
The rumour persists, though. Akiha thinks it's hysterical. Umeda finds it annoyingly illogical, which just annoys him more for the ridiculous irony of that. Perpetuating this stupid theory is basically an automatic firing offence for any of Umeda's science peons. Not because it pisses him off, but because it shows woolly thinking that clearly isn't appropriate to a scientist. If they can't even come to the logical, scientific conclusion that OBVIOUSLY UMEDA IS NOT A VULCAN, they are not fit to work under him as scientists.