Caught with a butt plug
I bought my wife a butt-plug. A small, pink, silicone plug which she initially objected to, but later came to enjoy it a lot. When she was hot and horny (and drunk) enough she would beg me to slip it into her and make her come while this little pink indignity was sticking out of her butt.
One day I was off sick at home, my wife was off doing her 24h shift at the hospital, and I grew so bored and horny that I started to experiment with some of our sex toys. One of them was the plug. I applied a liberal amount of lube and began to try and slide it in. Slowly. Delicately. Last thing I wanted was some literal emergency. Slooowly. At first all I felt was awkwardness and some discomfort, but as the plug buried deeper and deeper, I became more and more aroused. I began to fantasize about somebody pushing it into my butt against my will.
Finally it slid inside fully. The muscles, having never dealt with such situation, tightened and kept it firmly inside my ass. I was penetrated. I had a pink butt-plug firmly buried in the place where men lose their other kind of virginity. I almost came.
And then the doorbell rang. I panicked. I could try and remove it now, but I didn't want to risk any injury. I just put quickly my pants on and ran to the door in order to quickly handle the postman or whatever.
But that turned out to be my wife, who finished her shift early. I was standing there, blushing, butt-plugged and almost at an orgasm. I knew I could do only one thing that would not end in a complete embarrassment. I kissed her like crazy and gently forced her head between my legs. Before she could elaborate any protest, my dick was inside her mouth and few seconds later I came like crazy all over her face.
She didn't even ask why I did what I did. Under the pretence of having to clean myself up, I retreated to the bathroom and gently, slowly removed the pink bastard.
I haven't yet made up my mind if I'm going to tell her what happened.