My Wifes Sister

My wife sister never really cared for me. She always thought I wasn't "man" enough for her sister. Although my wife would always defend me as a loving caring husband she just didn't see it. Her husband was Mr. Macho football jock guy and she seemed happy with that.
That all changed when she found out that Mr. Macho was slipping it to at least two women in his office and maybe a third. After a late night tear-filled phone call to my wife they decided that she should come and stay with us for a while, at least until she decided what she wanted to do.
She arrived on Wednesday and by Friday had settled in. my wife and her were drinking wine and by the time I opened a second bottle for them they were giggling and whispering together.
I busied myself in the kitchen straightening up when I heard my wife's slurred voice call out, "Hey Kaaren, c'mere we need to talk to you."
I couldn't believe she would call me by my femme name in front of her sister and as I entered the room I found the both of them smiling at me.
My wife said, "Kaaren we need some attention, please give me some nice footsie love."
Giggling, my wifes sister added, "Oh yeah, me too....Kaaren."
The way she said my femme name made it clear that our relationship had just changed forever.
As I hesitated, blushing furiously, my wife said, "Well, get busy or do I have to put you over my knee and spank your sweet ass?"
My sister-in-law laughed as I slipped to my knees and removed their slippers.
She stopped laughing as I began to lick her pretty feet. By the look in her eyes it wouldn't be a one time performance.