The story written for me was How to Spot an Invert by aunt_agatha! It's a great story -- InuKai and YanaKiri with lots of great Inui-Yanagi interaction as they try to work out their relationships with their kohai.
Thanks again, aunt_agatha! I completely suspected it was you! I hope my request didn't make you too crazy -- it was a little involved, asking for two pairings at the same time. (So greedy, I know!)
In other news, Atobe is still hot and I still like cheese.