When traitorous magical knights roam the land, of course there will be some good guys going after them, right?  Well, sometimes the bad guys are actually the good guys.  In the original manga series The Seven Deadly Sins (17 volumes, 2012-present) by Nakaba Suzuki is about the fine line between good and evil in the form of a fantastical, action packed story in a time long ago.
The series follows a princess (Elizabeth) on her search for the legendary traitors to the holy knights (magical knights) called the Seven Deadly Sins (who supposedly betrayed the kingdom) in an attempt to find someone to stop the holy knights who she believes are tearing her kingdom down from the inside.  When she stumbled into a tavern, exhausted and on the brink of collapse, her journey truly begins when she meets the seemingly young tavern owner.
I really loved the manga series and look forward to the rest of them as I am sure there are many more to come.  With action, fantasy, and a bit of odd humor, this series has it all.  I loved the art, the ideas, and the secrets that hide in the story and would highly recommend it to anyone.  If you are looking to buy any of the volumes of this series, Barnes and Nobles, Amazon, and Books-A-Million all carry the series (although not all of them are translated into English) for a reasonable price that I believe is very worth it.  I would highly recommend this series to any and everyone.