Fic rec: the Worthyverse series, by tarnished
This is a four-part (so far) series from Tarnished. It's BDSM, D/s, powerful!Harry and bottom!snape, but unless any of those squick you to the point where you can't enjoy a very-well-written fic that includes them, this series is really all about Snape's emotional development after Voldemort's defeat.

I keep being surprised by the emotional intensity of this fic. I appreciate emotionally intense fics where the emotions are never explicitly spelled out - "show, don't tell", right? This fic is brimming with love, passion, hurt, comfort, pain, release and emotional breakthroughs , and it's nearly all expressed without words. I'm not into bdsm or D/s myself, so it's not that this fic is hitting any of my particular kinks - other than that for very good writing.

The fics in this series are, in order: Worthy, Owned, Transcendent, and The Alchemy of Change. The latter is new and is set a few years after the previous three.

All fics are on Tarnished's blog and are linked from here - http://tarnished.taintedikon.com/tags.php?tag=Fic:Worthyverse