While my wife was away, I was confessed to by my wife's sister and fucked her all the time.

"I've loved you since we first met you. But I've got married to my older sister...but I still have regrets," I was happy when my sister-in-law confessed. It's a house where both of us are alone, without a wife. There's nothing to get in the way. "If my wife doesn't come back like this..." I want to be so addicted to this relationship that I end up having such a dangerous delusion.