Really good science fiction romance. There's quite a bit going on in this story especially the with the conflict between the Collective and the Greys. At first I didn't really understand what was happening in this story, because I didn't read the first book in this series, so it felt a little disjointed. But, the author did a good job of bringing readers up to speed on what happened through some of the characters flash backs from the previous book. Lily's flash backs and Birdies journals were really helpful in keeping this reader from being confused. I felt that the main focus of this book was not on the romantic interest of the characters, but more on how to deal with the on going conflict between humans, The Greys, and The Collective. There's quite a bit of violence and drama throughout this tale and the alien presence was sometimes hilarious and scary. I will definitely want to read the previous book in this series, and I would definitely recommend this to my friends and family, and I look forward to what's next from this author.

Rosemary is the continuation of the story begun in Liaison. Lily is Earth's Liaison to the inter-dimensional collective. Lily's hybrid IBD daughter Birdie leads them on a journey to meet another like herself. Birdie and Rosemary will play a part in the collective's next challenge. An old enemy returns the IDB must negotiate with them to keep the peace and avoid a war.
Liaison was a short intro to this world and I liked it but Rosemary really built on that story in a great way. I like the character and world building done in Liaison, it really helps set the stage for this book and Rosemary can't be read as a standalone. Lily and Hunter are great MCs and I liked the evolution of Birdie as well. The plot was fun though there is a lot of lead up to and end that happens very quickly. There's also a part where Lily has a big freak out towards the end that feels like it comes out of left field and isn't true to her character. This series though is very unique and I love the idea that other beings could have a Liaison like this with a human. Lots of fun to read, especially anyone looking for a little sci-fi fun.

Aliens, hybrid-aliens and a threat to Earth
This scifi is firmly grounded on Earth - because the aliens are already here. Again as in the first book of the Desert Willow Series there is a new sharpening of conflict between the IDB (interdimensional Beings), allied with Earth, and the Greys who are out to harm Earth. The heroes who save the day are this time two young human-IDB hybrids, one of them a daughter of Lily who carried the day in the first installment of the series.
The book is cleverly construed: There is one strang of the story where we see the development through the eyes of human Lily and the second, the diary of the human-alien hybrid, where we get to see more and more of the alien world-view. I loved to get a deeper understanding of the IDB and the diary was a revelation. Another great feature was the trip to the bayou - I loved the description of lush nature and the quirky people living there - dialect, big hearts and all. The iuxtaposition of the verdant waterways of the bayou and the stark desert in New Mexico, Lily‘s home, was another highlight for me. The story didn‘t capture me as much and the end disappointed (seriously, dereliction of duty, come on).
So the writing is at times great, the story line is not as well-crafted in my opinion. Hence: 3.5 points

PS.: This is the sequel to Nat Burns, Liaison, the start of the series. If you must, you can read Rosemary as a stand-alone, the author connects many dots during the read but it is best if you start with Liaison before you read Rosemary.

Thanks to netgalley and Bella Books for the ARC. The review is left voluntarily.