Solo Thrills

My confession is simple really. I get off on the anticipation of being caught. It's not that I'm ashamed I masturbate, and I certainly don't deny it, I just decided a very long time ago it was something I did not wish to share with anyone else. I decided I was as good as I would ever be, and while I enjoy sex with my partner, the thrill of him or anyone else catching me sends chills down my spine.
I know in the mornings, while my partner showers, I can run my fingers to that special place and finish just as his footsteps enter the bedroom. I'll act like nothing has happened, strike a conversation, while my inner devil is smiling with delight!
And it doesn't just have to be my boyfriend, there's construction workers building flats just across from mine, and after careful observation I realized they were out of eye shot for a few moments at a time - cladding the walls before walking back along the scaffolding, past the window where they could look in at any moment and see me on the couch.
One time when I was a teen, I masturbated at a friends house as she went out the room to speak to her parents. The door was left wide open and the soft carpet made it difficult to hear her footsteps. However, the thrill was too much! Although not caught in the act I did wonder if she noticed the damp patch on my jeans.
I can't explain why I enjoy this, and it's not something that I've ever wished to explore in mine and my partners sexual moments, it's just a personal thrill that I selfishly want to keep to myself!