This past Christmas Eve my wife and father-in-law ran out to the store for some last minute things, leaving me and and my mother-in-law Kim to finish preparing for the 30 or so guests expected that evening. We worked quickly and opened a bottle of wine while we waited for the other two to get back from the store. After some time and the bottle gone my wife called and said they would be at least another hour with traffic. My mother-in-law gave me an evil grin and took me by the hand. She led me upstairs into the guest room muttering something about a special Christmas present as she got on her knees before me, rubbing my hardening cock as I undid my belt and unzipped. She proceeded to give my cock and balls the pleasure of her mouth and tongue. It was an amazing blow job made incredibly more erotic for the fact that my mother-in-laws lip's were wrapped around my cock. She took the first jolt of my cum in her throat, she pulled off gagging and held my cock close to her face as ensuing spews of cum coated her lips and chin. She giggled joyously and couldn't wait to look in the mirror. She rubbed my cum all over her face and lips licking her fingers the whole time. We heard the garage door opening and we quickly straightened up and hurried down stairs. I watched in amazement as Kim planted a big kiss on her husband's lips. I watched knowingly all evening as she would give me a slight nod right before she kissed or got cheek to cheek with someone. It was all quite amusing watching her and I look forward to our next party.