The best description for YMCK is 8-bit-jazz.

They make music that is generally called chiptune or 8-bit, as instruments they use mostly analog sounds from old console games. But when most of their colleagues use these sounds in more electronic way, YMCK use it a jazz instruments. You can clearly get the bass line, jazzy drums and various arrangement instruments like keyboards or probably brass. The whole music reminds of the 50^th smooth jazz especially the childish female vocals.

They have released two albums so far “Family Music” (2003) and “Family Racing” (2005) made few world tours and participated in some major electronic festivals. As for me their best success is a swing-styled song from the “Family Racing” album.