What is the nature of romeo's desire toward Rosaline?

He wanted to sleep with her. Benvolio asks Romeo "Then she hath sworn that she will live chaste?" (meaning she has decided to remain a virgin?). Romeo replies: "She hath, and in that sparing makes huge waste, for beauty starved with her severity cuts beauty off from all posterity. She is too fair, too wise, wisely too fair, to merit bliss by making my despair: She hath forsworn to love, and in that vow do I live dead that live to tell it now.