Well I guess the title gives the main theme right ?

And if you're asking yourself, Yes I've recorded the times I came on them, just haven't posted any because I don't really know if it would actually get any interest of anyone.

 The few times I've done it were amazingly exciting, I started with her period pads at first, she was speaking with my gf (her sister right) and like most girls speaking to eachother in fam saying "hey I got my period" - "oh ? you too ? mine started yesterday.. bla bla"

And that's when something tilted in my head. Something, (filthy for most) coming directly out of my SIL's pussy on a pad she was wearing all day ? What ?

My cock instantly twitched and that's when I decided to wait till she goes to the bathroom (as the living room was just 1 door from the bathroom, you can hear the scratch of the pad taken off her panties and put delicatly in the former plastic of the new pad (you might know that sound)).

Anyways once my SIL was done, I waited a bit (so it doesn't seem too obvious of anything) then I pretended I needed to take a sh*t. (Yeah her fam talks about it openly with no akwardness)

The the adrenaline started as soon as I locked the door. Went to the bathroom bin, lifted the lid and there it was. I took it out smelled it, and it smelled like raw pussy from a sweaty day, but didn't smell like fish (like some pussies can).

My cock was already out and hard, but had to concentrate on opening the pad rolled in without making that scratch noise with that plastic (as they are just on the other side of the door chatting). Slowly but surely succeeded opening it. Her pussy blood with what I guess is her pussy juice mixed together, my cock was throbbing like a mofo already precumming.

Then like a perv in his moment just started rubbing like an addict on her pad, still slightly warm I could tell, I was sky high but had to maintain silence. The rubbing had to be slow and controled. Managed to do so until they started laughing in the living room, that made it for me, hearing my gf with her sister laugh was the signal "they cannot hear you if they are laughing", I stroked harder still with controle, almost holding my breath. And fuck it, I came like all men should come. The ultimate forbidden relief on my sister in law's period pad. Felt guilty at first, but only lasted a sec.

 We went a few months or so later to her place again. And that time I took her dirty panties (after she just finished shower), same technic, same config. Opened the dirty laundry basket, rubbed the sh*t out of it. Soft, recent pussy juice, smelled it before, licked it a bit. Now everytime I get a comfortable occasion I try cumming in them dirty ones.

 So now that I've expressed one of my dirtiest secrets, tell me, would it be a thing  for you guys and girls to watch what no other person have seen yet from me ?