I was home alone only with my 2 year old son as my husband was in Italy for a couple of weeks work. I had forgotten that my youngest sister and her husband had had arranged to come over to use my computer because hers had died. I let them in and my sister got working at the PC and my brother in law sat in the lounge to watch TV. I was only dressed in my bed dress when they arrived and had been just lazing in front of the TV watching MKR. The lounge floor was covered in my sons Lego which he was playing with before he went to bed. I started to pick this up as he got down and started to help me. We were both crawling around picking up the blocks when I caught him peaking down the top of my dress, he just smiled knowing I caught him. We where nearly finished when he then pretended to accidentally knock the Lego bucket over causing a lot of the blocks to go under the coffee table. Sorry he said and then just knelt at the end of of the table as I started to pick the up again. Nice view he laughed as bent to get under the table with shirt gaping. (We had flirted in the past but always as a joke in front of others so this was new.) I played along and wiggled by boobs while reaching the farthest block until a nipple popped out of the neckline then stilled as he stared and smiled at me. I then turned to reach some blocks behind on the other side of the room. Stuart came in behind me and lifted my dress exposing my naked rear. I was exited and wriggled in front of him. Stuart stood up and pushed a chair against the closed lounge room door. then sat back down behind my and started massaging my ass, then between my checks across my anus and then stroked across my moistening pussy. He laid down next to me and told me on ride his mouth. I squatted over him and he started kissing my pussy, then with his tongue deep inside of and his nose grinding into my clit. I moaned as quietly as I could , remembering my sister a couple of rooms away as I cummed into his mouth. My turn he said as I moved off him. I undid his pants and slide then them to his ankles. As I started to massage his cock, he took my hand and put my middle finger against his anus. Finger me he whispered, as you suck me. I had never fingered a male before. I felt around inside feeling him squirm as I found his prostrate. I rubbed the spot as he exploded in my mouth. I swallowed, we kissed, and cleaned our self with some baby wet ones which were on the sideboard. He dressed. We then sat on the couch together cuddling in each other arms until we heard my sister call out that she had finished working. We have seen each other since at family dinners and such but haven't spoke about our encounter, only flirty comments saying he knows what he wound like to eat.