Title: Shire Morns series
Author: Elderberry Wine
Rating: NC-17
Summary: A (long) series charting Frodo and Sam's relationship from its beginning shortly after the Party to the start of the Quest.

Comments: Long is an understatement, but set aside lots of time and it is so worth it. Frodo and Sam go through the trials and tribulations of being together, and deal with the expectations of friends and family. Contains lots of beautifully realised secondary characters.

If you don't have time to dedicate to the whole thing, then Sweet Cider, at the very least, is a must-read.