Ok, girls have certain questions when it comes to deep-throating a cock to the hilt, and those questions are: "Do I swallow?" "Do I hold my breath?" and "How much more does he have?!" These are all valid questions, and she might be intimidated by it at first, but when she wants to know how much more, you tell her "To the balls!" And don't worry, she'll take it no matter how big it is!