ok so your probably in high school and you are just happy when any guy gives you any sort of attention. Let me tell you...be careful. guys this age just want to experiment and will play with your heart.
The biggest sign is HE CARES. like not the "I love you and nobody else cares about you except me" cares. no, I'm talking about the if you need anything I'm here and how I wanna help you feel better care. He doesn't just care about what's upsetting you but he wants to be apart of how you get through it.
He is understanding. This is a big one. Like a huge one. If you don't like something he does or say...he doesn't have to always agree abut he understands.
HE DOESN'T JUST WANT YOU FOR SEX! I am not going to get too in-depth with this one because I don't want to offend but boys are boys. They are horny and most of the time only say sweet things to you just to get in your pants. And it's really hard to know if he doesn't want that...it is basically like flipping a coin, unfortunately.
He respects you. He respects your beliefs, your body, you knowledge, and everything more. He doesn't try to pressure you.