WONDERFUL book! I really enjoyed both the story and the back-story very much. Because "Ship of Theseus" is a book within a book, the reminder that it is a fiction is ever-present, so it is difficult to immerse yourself within the typed words of the pages as if you were there (but it's still a great story). But the back-story, which takes place in the inserts and handwritten notes between Eric and Jen, is very immersive! It felt very real, and the entire time I felt like I was someone who had found this book of theirs and was piecing together their history. The development of their friendship, the events in their lives, their banter and flirting - all very enjoyable and it really draws you in. Both story and back-story are laced with the motif of identity: what makes us who we are, and how we change. A fantastic book and an ingenious style of storytelling. Highly recommend!