Previously, I've reduced the lime juice (to 20ml) and upped the cassis (to 30ml) in a quest to make this bittersweet 'n' sour aperitivo a touch more approachable...
I "made up" a drink like this when I was a bartender in Tokyo with no idea what I was doing. Mine was a highball that added Zubrowka and soda. For how young I was, I think it was pretty sophisticated.