What is this Song from Bleach?

[Maikeru-sama]

I am trying to find the song from Bleach from Episode 43.

http://en.wikipedia.org/wiki/List_of_Bleach_episodes

The song is playing when Mayuri is beating the crap out of his lieutenant (female) as he tells Ishida about the experiments he has done on her and Ishida is looking in horror as he does it.

[SonRyu]

I believe that is an unreleased track (so far); I don't recall hearing that on any Bleach album, as a track by itself or as part of another. It's probably another case of "track being too short to release". Happens all the time unfortunately.