Here you will find a list of Shoujo-ai and yuri anime, manga and visual novels. Please feel free to leave reviews and recommendations for people (and don't forget to use spoiler tags when necessary!). (List will be maintained by 13)
-Anime: A lot of content was changed compared to the light novel such as events, minor details, and characters. It starts off a bit slow to kinda settle the viewer in before increasing the pace to fit all the content in. It is well put together; however, the short scene after the Japanese credits I felt was completely unnecessary. The first time I watched it, I felt it ruined the ending, but now that I've watched it again, I wouldn't really say the same; however, I still don't think it was necessary.
-Manga: There's not much to say about the manga, since it was dropped for whatever reason, but it seems to follow the light novel quite closely.
-Light Novel: As previously stated before in a reverse-fashion, the light novel has a lot more content than the anime. There's a lot more characterization for each of the main characters compared with the anime. There is one line in a scene that I laughed at because it was written (or translated) in a cheesy manner "Hikari felt a single drop of nectar trickle from inside her body.
", but that's really the only instance. The pace is steadier than the anime, but isn't horribly slow. The ending I felt was better than the ending to the anime, and left the reader on a heartwarming note.
-Conclusion: Read the light novel if you are going to watch the anime, as both plots are different and complete. Or read the light novel if you prefer the original story.