<human>: Could you distill the essence of the text into 1-3 sentences?

Alright so there was this girl in my summer class that I didn't take care to notice until the last week of summer school. I barely talked to her but I did end up getting her number which was eaiser than I thought considering it was the 1st time I actually got a girl's number. (We'll call her Sally)

Sally puts her phone number in but forgets it so she checks her phone to be sure. After that I know it's 100% legitly hers so I feel proud of my confidence and achievement.

I text Sally's number saying it's me and then hours later her boyfriend replies to the text telling me to leave "his girl" alone. He then goes to saying how he talked to her about her giving me her number and that I need to stop talking to her.

I feel that she was genuinely interested in me. So what's there to take from this? Check up on the number later on, or just ignore the situation and leave it at that? Also is there a reason why she would do this, such as her finding me to be better for her. I didn't know she had a boyfriend at 1st which made it a bit awkward after finding out.
<bot>: Got a girl's number, her boyfriend responds. Why did she give go along with giving her number, should I just simply move on?