Dennou Kakugi Mephistowaltz

prodigal pianist morimiya francois permanently injures his left hand and his musical career is brought to an abrupt halt. he plunges into despair with no other interests or skills to live for, but amidst the darkness, he stumbles across his video game doppelganger and is quite forcefully introduced to the world of fighting games. where will this new hobby lead him?