Yeah, it's a nice take on the fairy tale "The Ugly Duckling". But there wasn't much more to the story. The world-building was basic, the two plot lines were Ori and Reynard entering a dom/sub relationship and Ori's first complete shift at the age of 21 and its repercussions. Ori's only desire in life is to be with his master (and to clean up behind him!) - exciting!
The BDSM is very light (well, the SM part is) and since Ori – as a duckling – is naturally inclined towards submission and service, there weren’t any boundaries that had to be pushed. Reynard, the hawk, said jump, and Ori jumped.
Also there was hardly any meaningful dialogue between Ori and his master. And you’d think people would tell him stuff or he would ask, but no. For the sake of the plot, Ori is one headless chicken.
Lastly, the whole shifter business made for some horrific new pet names. "Come for me, fledgling!" And I don't know about you, but for me it was a bit off putting to read stuff like "his shaft disappeared into the duckling's mouth".