It's the sister-in-law

It is my sister-in-law. She stands shocked in the doorway, one hand holding the doorknob, the other hanging at her side. Her face is red, contrasting with her white outfit.

She g-gasps my name.

I too am frozen, facing my brother’s wife, feeling embarrassed and ridiculous, although a part of me is too exhausted to care. I stare at her in her smart skirt and short jacket, and with the one part of my brain that is working, I realise that she has just got back from work – early!

Her eyes move from my red face and down over my naked, sweaty body, and I see her eyes widen suddenly as she spies the wet between my thighs and the lines of cum down my legs.

“I..I”, I bluster, tying to find something to say..

“What are you doing?”

I cannot deny it, but I cannot admit it. “I..I was just..”

“I think I know!, she says incredulously.

Did I spy a faint trace of a humorous look?