Kuro no tenshi (Vol.1) was Takeshi Ishii's 1997 first stab at the female assassin phenotype, carefully interbred with the attributes of yakuza revenge thriller and (as with Gonin), those of nail-biting psychological horror. It works for me.
There's one scene in particular that marks it out as something rather different- Ikko and her accomplice Zill from LA are holed up in a gaudy Tokyo hotel room when he suddenly bangs their boogie box into life. It's undoubtedly a phatt tune so he leaps onto the bed and starts breakdancing on the duvet. Moments later he joins Ikko at the foot of the bed for a beautifully choreographed dance sequence that somehow feels genuinely spontaneous and oh so Japanese.
The pair are supposed to be Japanese Americans and so are required to explete in English ("fuckin' a") and otherwise mumble anglophonically. The home audience gets subtitles, but it was all a bit Gleek to us.