This paper model is Elucidator, Kirito's primary weapon in the anime / manga series Sword Art Online, the paper model created by Kevin. This sword is a demonic monster drop from a boss on the 50th Floor that he wields along with «Dark Repulser». It was boosted to +40 by Lisbeth out of a maximum of 50.
Elucidator is a pitch black sword, evenly balanced and quite powerful. It has a black handle connected to a hand guard that is longer on the right side. Attached to this elongated area of the hand-guard is part of Elucidator's obsidian blade so as to better aid the user in retaining their grip on the sword when it is being used. The blade is completely black like the rest of the sword and the said blade is outlined in a light gray. A small cross is emblazoned on the flat of the blade, just beneath the tip. [Source: wikia]
You can download the papercraft template here [Note: If you want to rescale it, the password is "piraka".]: Sword Art Online - Elucidator Sword Free Paper Model Download [Box] [Gavitex]