Amethystine

Link to Ameth's journal: http://www.furaffinity.net/journal/7871323/

Fair warning, this is definitely NSFW. It's a very kinky conjoinment, merging, and TF story, and I do believe it earns the distinction of being a record-breaker in those genres. So be warned, it's not exactly a vanilla tale.

But if that's the content you've got a craving for, this is definitely right to your tastes, and it's got enough content that it'll keep you most pleased for quite a while. Ameth was kind enough to offer me a preview, and I gotta say, he really put in the time and effort on this.

And it's for a good cause: helping Ameth with some expenses.

Link: (as mentioned before, very much NSFW) https://gumroad.com/l/HQWfG