I was a little disappointed by this book. Even though I always manage my expectations with YA books, given the fact that I'm not the target audicence by my age but I greatly enjoy them anyway, this book let me down a lot. And that is because it had great potential.

The concepts explored in this book are great. The curse that Tamsin have, the magic system with these "sources", how different sources and witches approach magic were great. The characterization of both main characters was also really well establish, to their detriment. I'll explain why all of this was detrimental to the book.

The book felt too short for what it was aiming and that was my issue. Tamsin and Wren were good main characters, with a dynamic that I'd have loved if the book took its time with it. But it felt very shallow, rushed and not very believable; the baggage that both these girls were carrying with them was so well grounded that it felt too fast how they started to bond, even under dire circumstances. These concepts weren't explored enough to give me satisfaction. It was like "here are this cool things, but we don't have enough pages to talk much about them" and that made especially the middle part of the book boring. The writing also struggle with that. Sometimes things happened and they were so out of nowhere that took me out of the book and made me wonder if I just skipped a paragraph or something. That made me feel the worldbuilding really clumsy.

For my other big issue, I'll leave it as a spoiler:

The main "antagonist" was really underwhelming. I hope it wasn't the intention to surprise us that it was Marlena, because it felt really evindet from the beginning. The predictability is usually not an issue for me, because I like to see how we arrive there, and not the destination in itself. However, I feel the author took more time fleshing her out as a character and her motive than the actions in itself. I liked her resentment towards Tamsin and I like that by the end, she wasn't ready to forgive her. It was the highlight for me, because it speaks volumes on how hard these matters are and how is not easy to forgive someone, even if it is someone you used to love. But the way we got to her felt too easy, the steaks didn't feel high and even though the fight was kinf of cool, it felt like it was really hyped up during the book to just two or three chapters. The chase wasn't thrilling and I feel it is because the facing her was too short. If she had been more present as her present self, not just her diary entries, it'd have given her more chance to develop as an antagonist and exploit all that characterization that she had. Same as before, there was a lot that wasn't used in the end for me.

For the good: even though I didn't like how rushed the relationship felt, I still knew and wanted for the romance tothrive. Again, fascinating concepts. The way Wren, as a source, described magic was beautiful. Those were my favourite paragraphs, because I could basically feel what she was feeling, see and hear and taste what she was in that moment. It made me wonder and marvel at how rich this world could have been, given more pages to be created with more pacience. Also, for a character without any prior knowledge like Tamsin regarding magic, her ignorance didn't feel bothersome or annoying. I was in Wren's shoes and even though there was (logically) a lot of exposition, I liked how not absolutely everything was explained. The diary was a nice touch and I was intrigued everytime I noticed a new entry came. 

If you like magic, it may be an okay book. However, it may also feel a little disappointing like it felt to me. I'd say it was a quick read that midly entretained me for a while, so that is why I up to 3 stars and didn't leave it in 2 stars.