When I say I love this series, I truly mean it. From the very first page of Daimon to the very last page of Sentinel, I have been firmly enthralled, riveted, and glued to this story and cast of characters. The Covenant series is truly a legend among books in my opinion. Not only is the story genuine and engaging, the characters are easily some of my favorite YA characters of all time. Jen sparked my intrigue with Half-Blood, had me torn in Pure, captured my heart in Deity, (got me all emotional in Elixir), blew me away with Apollyon, and she gave one hell of an amazing conclusion with Sentinel. Sentinel stands out among its predecessors by really drawing out your emotions and sensibility. You've watched these characters go through so much and when you finally live the epic conclusion, you're definitely left with a feeling of completion and satisfaction. At least, I did. 
 Alex has grown so much as a female character throughout this series, it just amazes me. She'll always have that inner snark and humor that I love and adore, but she's also become more responsible, sensible, and mature; especially considering all that she's been through and what she faces in Sentinel. She's still my favorite YA heroine, that's for sure. I loved how real Jen kept Alex, especially after what happened with Ares in Apollyon. I got to see various sides of Alex I never thought I would and I loved it. The ending really got me all kinds of choked up and just seeing Alex handle it all just really made me want to hug her. 
 Aiden. Oh, Aiden. I can never say his name without a loving sigh afterwards. That man is just pure perfection. You all know how much I love him, and he doesn't disappoint in this book. The love, care, consideration, and respect he has for Alex simply radiates off the pages and I can't say enough how I wish this guy were real. Finally embracing their relationship after what happens in Deity and Apollyon, I loved how open and affectionate he was to Alex and how much he valued their love. You get to see a different side of Aiden here and I actually really liked it. I think it made him seem more real and really, if you ever doubted just how much he loves Alex, by the end, you'll understand. This guy?! Ugh, I swear, I'm forever and always, a St. Delphi girl! 
 While I will say I live and breathe the romance between Alex and Aiden, I also loved Jen's take on the mythology and how that aspect was a strong theme throughout all her books, but especially becoming more and more prominent as the books progressed. You definitely get your fair share of Gods and other mythical creatures in Sentinel and I like how Jen breathed new life into these age-old beings. I loved Apollo. Every time I read one of these books, I want to dive into Greek mythology, re-reading the ones I know and love, and reading those that I have yet to discover. 
 Let me also say that Seth truly won me over. I was hoping that Seth would redeem himself after all he did in the previous books and I can safely say he did that and so much more. He really surprised me quite a bit in Sentinel. In the other books, we got a playful, sexy, arrogant, and sometimes challenging Seth, but I always knew, deep down, he was a good guy. How good, is still yet to be seen, but he I liked the direction Jen took his character and his relationship with Alex takes on a whole new level after all is said and done. Honestly though, by the end of the book, I just wanted to hug the guy. I love that we've only barely scratched the surface of Seth, yet I care for him so much as a character. I can't wait to know more about him. 
 I truly never wanted this series to end, (any chance to read more Alex & Aiden scenes is fine by me) but I am very happy with the way Jen ended it. Just thinking about this book and this series is getting me all emotional and making me want to re-read the series even though I literally just did that not too long ago. I tried really hard to savor every word and page, yet also wanting to fly through it so I could see what would happen next. Sentinel is everything you've come to expect from Jen and the Covenant series, and so much more. You get love, action, drama, friendship, all the crazy supernatural stuff, a touch of bittersweetness and tons of humor and entertainment. I can't recommend this book, and this series, enough.