Preparation: Shake all ingredients over ice and pour.
General Comments: Dear me, no. There's an art to get sweetness and sourness working together, and it takes more than adding something ridiculously syrupy to something sour. Rather than working together the crème de cassis and the grapefruit juice create some kind of hideous comment on Heisenberg's Uncertainty Principle; you can't identify the mediocre sourness without losing it in cloying syrup, and vice versa. Occasionally the midori shines through, presumably as an attempt to apologise, but it's nowhere near enough.