Schwarz is the bodyguard/assassin faction who works for Reiji Takatori, leader of the Takatori clan and an all around not nice guy. Schwarz thinks that they and Reiji will take over Japan, and then the world. They are probably full of crap. They also don't like competition, which is why they plan for Weiss and Schreient to end up dead. Can nothing stand in the way of Takatori, Schwarz, and their evil plot?! Well, yeah. Duh.
See, after Farfarello accidentally kills Ouka (Reiji's daughter), Takatori flies off the handle, blames Schwarz for the deaths of ALL his children, and sends them packing. This doesn't stop them, of course, as they have their own agenda...
Schwarz means "black."
