DEF.MASTER is formed as a side-project of ROSEN KREUZ vocalist YOU-MI and GULT DEP keyboardist EBU.
V. YOU-MI / K. EBU
By 1992, DEF.MASTER had expanded into a five-member band.
V. YOU-MI / G. NARASAKI / B. TSUYOSHI / D. SHIGEO / K. EBU
All of the members besides YOU-MI and EBU leave, and support members join.
V. YOU-MI / K. EBU / Support G. Fujita (藤田) / Support B. TAKE-SHIT
DEF.MASTER revert back to their original lineup of YOU-MI and EBU.
V. YOU-MI / K. EBU
DEF.MASTER disbands.
DEF.MASTER is revived.
V. YOU-MI / G. watanabe / B. HIROKI / D. C.J. / K. EBU / K. ch@ppy
DEF.MASTER disbands again.
DEF.MASTER was a non-vkei project. They were active from 1989 to 2011 and are now disbanded.