Summary
From Tokyopop:
To survive a fatal train wreck, Sekai Maihime is thrust back in time where she discovers she has hidden powers that are connected to a doll, S. She is both aided and limited by Ss vague (but kind) guardian, Sovieul, who is the cause for Sekais presence in 17th century France. Sovieul vows to protect Sekai, but offers little information as to why these strange events are happening.
Unfortunately, they encounter Machiavello (also referred to as the Devil) who looks a lot like Sekais childhood friend and love Midou. Machiavello covets the powers shared by Sekai and S so he may obtain the power of the Devil R. Sekai only wants to find Midou and return to her time, but shes constantly hindered by her conflicting desires with S and by Machiavellos attempts to obtain her body. To find Midou, Sekai must cooperate with S and Sovieul to traverse through time while avoiding Machiavello.
More details