My sister's BF wants to lose his virginity to her

The young guy has been dating my sister for a while now and he's been eager to take their relationship to the next level. He's been patiently waiting for the right moment to pop the question, but something tells him she's not quite ready yet. He's been trying to figure out how to bring up the topic, but every time he tries, she seems to brush him off. One night, as they were laying in bed, he decided to give it one more shot. He brought up the subject and she seemed to be more receptive this time. She told him that she was ready to have sex, but only if he was prepared to lose his virginity to her. The thought of it made him extremely excited and he agreed without hesitation. He had been waiting for this moment for a long time and now it was finally here.