When a guy is genuinely interested in you, he will give it away in a variety of ways. Where women are subtle, men tend to wear their intentions on their sleeve. There are some cases where men can be manipulative in that they try to lie their way into your good graces for the sole purpose of getting into your pants. But for the most part, men can be pretty straightforward with their intentions, and you can find it a bit easier to check whether or not he wants something serious between the two of you. When a guy is into you, he will hold onto things you said, things you did, and things you like. He will want to know everything about you. A guy knows that getting in with your friends will earn him brownie points, since your friends will most likely tell you what a great guy he is.