Oooh that's an interesting one. Since Coeus likes to take kind of any opportunity to avoid the work he is supposed to do I think that if he woke up feeling a little under the weather he would stay buried under his sheets until Hunter would come to drag him out forcefully thinking he's just being lazy. It would probably take Coeus burning up/nearly fainting/vomiting for Hunter to believe he is truly sick lol (to be fair the guy looks ill at his 'healthiest' so it's hard to tell when he actually isn't well + he isn't good at asking for help (though there's little he desire more than being cared for))

By then he would probably get put back to bed (and have a snarky remark to say about it) and Hunter would pretty much put on the same grumbling and complaining he does with Gage, except with more groaning about how he's not being paid to be a damn fucking nurse, but he would do what he can for Coeus to not feel like shit/die/get better as soon as possible :'-) I think the degree of letting down this wall would vary depending on how sick/out of it Coeus is, so say if he had a pretty bad fever and was barely conscious Hunter wouldn't bitch that much and might actually do things like gently get his hair out of his face, run his fingers through his hair, sit on the bed next to him… Hunter has a real nurturing streak under his gruff façade and it's only getting worse with age lol

Bringing up possible trauma from the quarantine is interesting, though I think Coeus would less fear to get others sick and more fear dying alone: if he was really feeling like shit he would probably grab Hunter's wrist if he tried to leave the room and plead him to stay (tbh, even if it was mild but still enough to stay in bed, I think he would feel a pang of anxiety/sadness at being left alone, so he'd probably try to get Hunter to stay in roundabout ways that would make it look more like he's pestering him). Despite living his whole life not really caring wether or not he was alone the whole quarantine experience instilled both a new need (that he perhaps had simply ignored/not been aware of) and a new fear in him, and since he truly does not have the best health in general, this fear tends to flare up when it declines.

Now if Hunter was the one being sick, he would be fucked lolol he'd just lock everyone in a room so he could fucking rest