Author's website: Intimations
Rating: "Mature audiences" -- people have sex. Good sex.
I'm kicking off recs with this story because it's one of my very favorite House, MD fics. In this fandom, it's difficult to couch initiate internal character development through external plot because the external plot (canonically) is heavy not just on medicine but on obscure medicine. What Shalott does here is take the basics of a disease and use that to craft her plot. (I have no clue if she's a medical professional or not, but it sounds like she does her research -- not that I would know otherwise.) From there, her character interaction is sharp and true to established character, and allows her to explore the permissions and limitations of an existing relationship between House and Wilson.
It's worth noting that every time I go to the page to get the URL to pimp this fic, I wind up re-reading it. It's just that good.
PS: Hi, I'm Smitty and I'll rec just about anything I read that I think is good, including House/Wilson, House/Cameron, Duckling fic, gen, het, slash, PWP, plot, and a partridge in a pear tree. But I have never met a really well-written partridge in a pear tree.