Oh, fuck. This would be SO easy if I had any talent at writing. :headbanger:
Dokuro comes into Sakura-kun's life because he invented something that makes people immortal, with the side effect of keeping women at the prepubescent stage because, apparently, the future Sakura-kun is a friggin' pedo.
Orochimaru invented an "immortality" jutsu, and IS a friggin' pedo... albeit likely a homosexual one.
I imagine this would work best if Dokuro was assigned to murder Sasuke, but somehow fell under the same "fangirl disease" that afflicts the rest of the idiot girls of Konoha. So, she does murder him, but can't resist resurrecting him.
I think it would be very therapeutic for the audience to read, don't you? Might give an author the chance to use some of the 101 Ways to Kill A Sasuke.