Pleasure Unbound is the #1st book in Larissa Ione's Demonica series. Ione creates a new world where demons, shifters and vampires live alongside the humans and are out in the open. There is a human group called the Aegis or the Slayers, who are in charge of protecting humankind from the monsters, (Though very early in the novel the axis of good and evil starts to shift..)
Larissa Ione developed a very rich and detailed demon world, with original, previously unknown species, special traditions and customs. The reader may feel a bit lost at the beginning faced with so many unknown terms as the Demonica universe differs significantly from the usual UF or paranormal worlds, but the glossary hellps a lot as well as Ione's explanations. It feels like you ahve thrust in the middle of events and after the whirl of happenings calm down you get a slow introduction to the world and its reasons. It is clear that Larissa Ione put a lot of thought and research into her universe and it shows in the details and layers of the story.
Eidolon (by the way what a great demonic name is that!) is the hero, a succubus demon, a breed whose life revolves around sex. But E is a serious, responsible (and of course drop-dead gorgeous) doctor, he is 3D, has depth and history. He is considerate, the ideal man of many women, who doesn't fall for a generous, kindhearted and sexy as hell doctor?
Tayla is a slayer. She is a great fighter, set in her ways and stubborn! She has a lot of issues, so E not only works on mending her physically but plays psychologist too. These two together not only sizzle but combust!
I'd rather say this novel is more paranormal erotica than romance. It is not for the faint hearted: there is a lot of graphic and hot sex scenes (and I'd bet there will be even more in the next books, as E's brothers are more reckless and adventurous).