Most will likely say Chloe (Meg Tilly) -- and she has her appeal -- but I'm going with Sarah (Glenn Close). While she's never shown in scanty apparel, like Chloe, her shapely body is obvious.
shareChloe.
shareMeg Tilly definitely, she was only 23 at the time, and you can see why she had a bit of run in bigger budget films after this (shame she missed out Amadeus). I like Chloe too as she's not as open and more mysterious then the others are.
shareThey went out of their way to show off Glenn Close's great ass in the kitchen dance scene, but that wasn't enough for me to see her as an "alluring" overall package. I put her in the same cubby-hole as Meryl Streep and Sigourney Weaver; certainly not ugly, but... a little too harsh in the face to be what I personally consider attractive.
Yes, Meg Tilly is the obvious choice. JoBeth Williams wasn't particularly stunning, but I'd still take her over Close.