There's no one-size-fits-all answer to this question as it depends on various factors, including the girl's personal preferences and schedule. However, here are some general considerations:
Be Prompt: If you're interested and available, responding relatively quickly can show that you're engaged and interested in getting to know the person.
Don't Rush: At the same time, there's no need to respond immediately if you're busy or unsure. Taking a little time to craft a thoughtful response is perfectly fine.
Context Matters: Consider the context of the message and the overall conversation. If it's a simple greeting or a casual question, responding sooner may be more appropriate. If it's a more significant topic, it's understandable to take more time to respond.
Be Genuine: Don't play games or intentionally delay responding just to seem aloof. Be genuine and authentic in your communication.
Communication Style: Some people prefer to have longer intervals between messages, while others might enjoy more frequent back-and-forths. Try to gauge the other person's communication style and adjust accordingly.
Life Commitments: Everyone has different commitments and responsibilities, such as work, studies, or personal obligations. If you're busy, it's okay to communicate that, so the other person knows what to expect.
Interest Level: If you're genuinely interested in getting to know the person better, showing that interest through timely responses can be appreciated.
Ultimately, there are no strict rules for how long you should wait before responding. It's more important to be authentic and considerate in your communication. If you're interested in the person and want to keep the conversation going, responding within a reasonable time frame can be a positive sign. However, if you need more time to think or are busy, it's okay to take your time and respond when you're ready. Communication is about finding a balance that works for both individuals involved.