Sister In Law

My sister-in-law gives me blowjobs when she visits us. It started as a bit of a flirty joke but now she's straight up for it, every time, she's a really horny girl. The first time was a hand job but it shot on her clothes and made a mess. She told my wife that she had spilled some drink. It's always quick and clean, all in the mouth and swallow. The extra exciting bit is that my wife is always around at the time but doesn't know.
XEF