I am sure that I'm straight, but...

I was a senior in high school, and had been dating my best friend's younger sister, for a few months.

She was open minded and we tried most of the activities, that typical couples like.

One afternoon, my friend and i were playing xbox, and he started to tell me that, he and his sister are very open and share a lot of things most brothers and sisters, wouldn't want to talk about. He told me his sister, often talks about how happy she is dating me, and that we have an awesome sex life. It was a little weird, hearing him say that about his sister and I.

I just, told him it's cool that they are so close. I got the impression that he wanted me to ask what his sister, likes most in bed, but i ignored that.

After beating around the bush, for a few minutes; he told me she liked anal the most, even though she thought she wouldn't like it when i asked her if she wanted to try it. I told him that I was glad she liked it. "She said it was the most amazing sensation, you first put your dick up her ass", he said, still seeming like he had something on his mind.

He asked if I liked doing her in her ass, I told him i had to admit, being deep in her ass was my favorite too.

After he heard that, he stood up and handed me a bottle of lotion, before i could ask why he just gave it to me, he pulled his pants and underwear down and got on his hands and knees on the floor, asking me to take it slow, because he was a virgin. If he had brought it up any other time, I would have ask if he was joking and change the topic.

Holding the lotion and seeing his asshole, it was to hard to resist. I took off my jeans and boxers, if I had any second thoughts, my cock would have talked me into it. By the time I was naked, my cock was painfully hard.

As i moved closer in behind him, i began to stroke some lotion onto my erection. Then i rubbed some lotion onto his hole, slowly slipping a finger in, just like i did with hi sister. He moaned a little, and i could see he was rock hard too. I began rubbing the head of my dick, in little circles around his opening, by now we were both very excited.

I began to slowly push against he hole, gradually increasing the pressure, I told him i couldn't believe how tight he was. This made him rock back against my cock, pushing me about two inches into his ass. I stayed still so he could get used to it.

When his asshole stopped spasming, trying to push me out, i began to slowly push in deeper. Before i knew it, I was balls deep into him. I loved how it felt, and got hotter feeling my balls brushing against his ass cheeks. He told me to hold his hips, i wondered if his sister, had told him, i liked holding her that way.

I began to slowly pull back out, until the head, was almost popping out, then I pushed back in again. I slowly took my time, because it was his first time, and i loved feeling every inch of my cock, slowly entering him.

I began to go faster, when i saw him stroking his dick. After a few minutes, I was going hard and fast. I felt close, so I pulled out.

I gave him one last thrust, penetrating him and going deep, in a fraction of a second. I began to pump every last drop of my cum deep up his ass. While I was still cumming, he moaned, and began shooting his cum onto the floor.

I pulled out, both of us out of breath, and him thanking me.