RKD-EK9, a one-shot manga, will feature in the December 2014 edition of Jump Square. The duo behind it are both well known to the Death Note fandom.
Takeshi Obata famously illustrated Death Note too, while Nisio Isin (aka
NisiOisiN), penned the spin off novel Another Note.
As yet, there are no further details about RKD-EK9. I guess we'll find out more when the issue reaches our stores on November 4th 2014.
(With thanks to Logan for the heads up here.)