I think I can do that with my LipTopHangeyDowney morph set a bit negative, I'll try that.  Meanwhile here's a quick try at a Fairuza Balk-like mouth, accomplished with: built-ins LipBottomEdgeHeight (-.3) LipBottomThickness (.3) LipBottomWidth (.75)

mine
LipBottomTrapezoid (.1)
LipTopHangeyDowney (.45)

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