My Quiet Sister

I'm the oldest of three at 31, I've a sister 28 married two children and the youngest 24, she is so quiet you forget she is around. My quiet sister got a job working close to me in my new hometown. Rents are high and I bought a house instead of renting, putting all my spare cash into paying it off. With my sister living with me didn't impact my lifestyle all that much at first. Our parents live close to our other sister, so we're off their daily radar you could say. My sister's job gives replacement time instead of paying overtime. She had worked overtime and once it reached a day's work level, she got a paid day off instead. I usually work from home, feeling horny and had slept late, I got up walked around naked. Thinking my sister was at work, I started masturbating only to be caught cock in hand by my sister. She was bemused at first but got a bit horny herself. One thing led to another and now she shares my bed every night, I'm quite happy to fuck her, not that worried about getting pregnant. She is very efficient and makes sure she is always protected.