Sister makes a deal

I'm Damien 26 finished university and started a great job, stilling at home and no good with girls. My own sister Renee 23 calls me a nerd, she is going to the same university as I had gone too and still lives at home. My parents Patrick and Trisha own their business and do quite well from, my father won a crystal vase from the local chamber of commerce. Which he is very proud of and while our parents were away last month, Renee went out and partied on getting home very late. She didn't turn on the lights and being a little drunk she knocked the vase off the mantelpiece and it smashed on the tile floor at the fireplace. I heard the noise and turned on the lights and saw what my Renee had done she was very sorry for what she had done. But she was also drunk and I told her to to bed and I would clean up the vase. In the morning awoke and went shopping, Renee was still asleep, I checked several shops looking for a vase like the broken one. On my third try I found the exact same vase and it was quite expensive $135 and the only one they had left. So I bought it and replaced it on the mantlepiece. Renee was already up and feeling the worst for her night of partying. Renee would have to pay me back, but she didn't having any job and lived off the allowance she got from our parents. So I expected she wouldn't pay me back anytime soon, but being the nerd I am I save my money and am not short of cash like Renee. I thought a few times about hiring a hooker to lose my virginity, but wasn't brave enough to try it. Renee was grateful for me replacing the vase and said she would pay me back, I had only done to stop our father going nuts over it. Anyway our parents got home mid afternoon and everything was okay. Three days later I was home just after finishing work, Renee was over a friends studying. Patrick was still at work, my mother Trisha asked who had replaced the vase. I tried to look like it was a surprise to me that it had been replaced. But Trisha can read me like a book, anyway I told her everything and she said she wouldn't tell Patrick. I thought the new vas was perfect copy of the broken one and so asked how she knew. It was simple she had knock it and got a small crack in it and she pointed towards the wall so it wouldn't be seen. She was herself going to get a replacement and had got off the mantlepiece to see if it had marks to identify it. That when she noticed it was a new one and so she asked me on my getting home. I told her I had promise Renee not to tell and she said she wouldn't talk to Renee about. But would have a go at her over going out late partying and let her think a neighbor or someone had seen her out partying. Renee came home and Trisha had a talk with her about partying till after midnight and didn't mention the vase. Renee still thinks I hadn't said anything about her being out or breaking the vase. Then both parents went away again and Renee and me were home alone again for 3 nights. I thought Renee might go partying and thought if she did, I would put the vase somewhere safer. But she didn't go out and came to me saying it's time she paid me back for the vase. I looked at her and she then undressed in front of me and was standing completely naked in front of me. I was shocked and she took my arm and led to my bed and undressed before having me lay on it. She worked her way down my body and on getting my cock started sucking it and I blew in her mouth. She just swallowed it and kept sucking and managed to keep it hard. Then she mounted me and rode me until I blew my load again inside her. She stayed the night with me and we fucked several more times before our parents got home. I was quite happy with her repayment method and considered the debt well and truly paid. Renee seemed to enjoy my cock and every time our parents are going to late home or are away, she come to me and fucks me. She says its because I let her take the lead and do whatever she wants. If she likes that I let her lead anytime she wants sex.