"To curb my pyro-enthusiasm... be less of an ass," she laughed, actually semi-serious, despite the jest. "Maybe those two go hand in hand," she sighed, the happy relaxed kind of sigh, as she rested her cheek against his chest. "Spending more time with Dawn would also be g--"

...and the reason for this sudden cutting off mid-sentence is because in turning her head, she treated herself to the tail end of Angel and Cordelia kissing.