The girl can also end the H-scene h

The girl can also end the H-scene herself. Reasons vary. She may end it for her own personal needs or because you haven't made her come at all. Also, if she does not have the Lewd trait, if someone else comes up, she'll feel embarrassed and end it. It also seems there might be some sort of "invisible timer" that will auto end the H-scene after a certain amount of time has passed. But as long as you've made her come at least once, she should be happy with her comment.