A Brother Sister relationship

Before I start I just wanted to tell you that I wanted to write a fictional story with character development and a long story line. Therefore, in some of the parts there will not be that much sex. However, it is imperative that you read all of them so that in the parts when sex plays a large role, you will not miss a beat.

This one, is the intro, so there’s no sex

Hey! My name is Jack. I am 5”11 a little skinny, blonde hair brown eyes. I am not so muscular but I still happen to be pretty athletic. So despite my average body, I still get ogled by the girls in my junior grade. I’ve had some flings with a bunch of these girls back in junior high and in freshman year, but my sex life has been stunted by the intrusion of my twin sister, Amanda when we were sophomores. We never went to the same school, but after she was harassed by some drunken dude at a party in her school, my parents decided that she needed someone to look out for her in school. So they transferred her to my school.
Amanda in 5”7 skinny just like me, brown eyes and flowing blonde hair that goes down to her shoulder blades. About five years ago she began to sprout round tits that have since blossomed into, pretty cute breasts. I shouldn’t know this, but when the cleaning lady put my sisters’ silk black Victoria’s Secret bra (which I never would have guessed she would have) in my hamper I checked it out and it was 32 B. People have always said she was pretty attractive and I have to agree, after all we are twins so if she is hot, then I am too!
Well since Amanda has been switched schools, she has become popular so quickly, that she somehow is good friends with all of the different cliques. They all know her and they all love her since she’s just a sweet girl who always has a smile on her face, while at the same time is athletic like me and also pretty smart. It’s fair to say that she was good at everything, which is why all the guys also wanted to get to know her.
Over the last two years she had been with a few guys, some o them my friends others not, but I had told her that she better not let me catch her with anyone I knew. She had been good with that as she didn’t want to hurt me in any way. As for me, every time I’m getting anywhere with a girl, she always says that she wouldn’t want to mess up her relationship with my sis, so we better stop there. Somehow my sister still got laid, while I had to jerk off to satisfy my teenaged-horny attitude.
Anyway, this particular story begins about two weeks ago; right about when winter became spring and the weather outside got a little warmer. As I cam home from school after basketball practice, I was in desperate need of a shower. Obviously because I was all sweaty but also because I needed to jerk off after watching the cheerleaders perform their routine right next to our practice. There was this one cheerleader Jessica, I think the assistant captain, that I had been very into my entire life, but to no avail as she was always with another guy, or just too elusive from me.