The PASSION she feels for him is agressive even in the physical sense of the word. Fosca wants him so desperately that you can do nothing but understand her and also feel what she feels. Unrequited love here is a powerful force out of control. The darkness in his relation with Fosca has its reverse with the clarity in his relation with Clara. She is beautiful, sensual. The "usual" object for a man's affection. But through the novel this oposition is changing in a subtile way. Because finally what Fosca offers is pure love. With total surrender, yes, but giving everything in exchange.
I always recomend to read the book in Italian, but this translation is a good one. And if you want to make this reading a memorable experience listen Stephen sondheim's musical "Passion". His adaptation is perfect. If you like Wuthering Heights or Jane Eyre this book wil be one of your favourites
