This was one of those things I had on 10-15 years ago as background noise while totally invested in some Gameboy game and ended up watching bits and pieces of. May have been a movie, a mini-series marathon (I do remember it being oddly long) or a multi episode story arc of a running series at the time. I have no idea what channel it may have been on but my guess is Sci-Fi (definitely pre-SyFy).
The only details I remember are the one mentioned in the question itself, of a girl being slid down a narrowing tube as a means of killing her (don't remember if she actually died), and one character (possibly the same girl) using "Wicked" as a sort of catchphrase. If I recall correctly the show had a sort of dystopian future feel and a dark goth aesthetic. It definitely seemed 90s or early 00s but my memory is a little fuzzy there. The work in question was in English, but i'm not sure from where as I don't remember what accents, if distinctive at all, the characters spoke in.