Suda 51 and Grasshopper have teased one of their future titles, coming out sometime after Killer is Dead, with a piece of art showing off a very familiar character.
As any No More Heroes fan will tell you, the character bears a striking resemblance to Shinobu from the same franchise. The way the lips and hair are drawn are too similar to be more than a coincidence, not to mention that like the girl in the artwork, Shinobu uses a Katana for battle.
While the flower isn't too similar to the one Shinobu wears it's speculated to be another hint towards the character being Shinobu. Suda51 was waiting for the next Nintendo console to work with for No More Heroes 3 and confirmed Travis's story was done with NMH2 so it makes sense that Shinobu would stae as the main character for NMH3. We'll just have to wait and see.