In my GF’s parents kitchen [MF]

I’m sitting at the dinning table in my ex’s kitchen. My hand laid palm down on my knee with my thumb straight up. My ex has a convenient hole in the crotch her jeans, she sits on my knee and my thumb slides inside her. My thumb is now all the way in and I start with small circles and work up to flicking her cervix, meanwhile she’s now grinding down on my thumb to streach the opening of her pussy wide. She’s really getting into it when her mother walks in and we both instantly stop moving, but she does not get of my thumb or lap. Her mum walks over and sits down next to us and we start chatting about stuff, all the while my thumb is still all the way in. Now because I’m a cheeky shit as my ex is talking to her mum I decide it would be highly appropriate to flick her cervix again mid word :) she instantly develops a stutter, but quickly recovers continues like a trooper. This goes on for about 10 minutes where I intermittently “interrupt” my ex’s concentration before the conversation winds down and her mum leaves the kitchen. Her mum isn’t even out the door yet when my ex starts grinding down really hard, hard enough to cause me pain which I dutifully ignore and keep flicking her cervix. I now have a wet patch on my knee and my hand is soaked with her juices. Her pussy starts to contract and squeeze my thumb and she explodes, silently of course, she slides of my thumb and sits down next to me spent and with a massive grin. I now have the problem of a wet patch on my knee and a soaked hand. Now there’s nothing I can do about my jeans, but my fingers go instantly into my mouth and I lick her juices of my hand. I don’t clean off all my fingers because I extend my hand to my ex and she cleans the rest of her juices of my fingers.