Well anything by Forthy, Tallymark, and RosieB is a good start. Fantastic authors, with fantastic stories. My main favs so anything that they've done is worth looking reading, they're here on Dokuga and they rock, so yah, must reads as in anything that they've written.
Another great author that's a bit unconventional but fantastic is Trouble In Shangri La. Absolutely adore two of their ficlets, Into the Blue, and Embrace the Silence. You will be glued to your seat. They're wonderful works. Unfortunately both works are rated MA so no YIMs thank you.
Into the Blue
Rated MA, No YIMs, and it's basically about a merman Sesshy who finds Kagome whose the equivalent of a marine-biologist.
Embrace the Silence
Rated MA, No YIMs, and it's basically the story of Sleeping Beauty but Beauty = Sesshy in modern times, and Kagome acts as his nurse in a hospital. He's asleep for quite alot of the ficlet XD, but he does eventually wake up. The story has alot of medical-references, and procedures like putting in tract-tubes etc, stuff that nurses do but there's a supplied glossary in most chapters to explain the med-stuff. I absolutely love this one purely for the detail, the emotional journey for Kagome, and Sesshy being all sleepy and pretty, if a little sad here and there.
Enjoy
~ Pyre