The Nakajima "Ki-201 Karyu" was a Japanese jet fighter project designed during the final stages of World War II which was never completed.
The Karyu began as an in-house project by Nakajima in early 1945 to apply what was being learned about jet aircraft from the Nakajima J9Y "Kikka" attack aircraft to a fighter design. The Kikka had been inspired by the successful German Messerschmitt Me 262 "Schwalbe", but the similarities to that aircraft were limited to general configuration. On the other hand, the design team led by Iwao Shibuya based the Karyu far more closely on the German aircraft, which had already proven itself quite formidable.
Nakajima attempted to interest the Imperial Japanese Army Air Force in the aircraft, and seems to have succeeded at least far enough to have had an official designation ("Ki-201") applied to it, but at that point, the Army had already decided to pursue derivatives of the Mitsubishi J8M "Shusui", designated Mitsubishi Ki-200 "Shusui" and Mitsubishi Ki-202 "Shusui-Kai", as their way of fending off the Boeing B-29 "Superfortress" raids. It seems that the Navy was also approached, but displayed no interest whatsoever.
Undaunted, Nakajima continued development, anticipating test flights by December 1945. Most sources agree that work on the prototype had not yet begun by the time of the Japanese surrender.