Various people in the game seem to think so too. Additionally, another point should be made in support of this. Paint pictures of everybody. Then sell them. They're worth different amounts of money, you'll notice.
Female portraits are worth more than male pictures.
And Opera's picture is worth more than any other female's. But it's food for thought. Even if she's not as proud about it as Celine, that fact remains that the other three females don't hold a candle to her where measurements are concerned. The PA where her and Claude bet on whether a man or woman will come out of the store is the easiest to find. You'll hear her mentioning something about making a bet when she knows what the outcome will be.