The Bottomless party reminded me of similar days
My ex girlfriend and I used to spend weekends together at her house as we worked in different towns during the week.
We started to spend the entire day naked but had to start wearing a T shirt or top so neighbours and passers by did not suss what we were up to. This state of being respectable on top but exposed below heightened an already horny state and we jerked each other off constantly throughout the day.
Even the most routine household chores would be interrupted by my girlfriends hand reaching out to pull my foreskin back and forth while holding my sack and caressing me to spurt for her. She would push enough to uncover the head and smiling coyly she would jerk me off slowly. I used to come on her legs or in her hand to sounds of her encouragement. I could just stop my girlfriend in her tracks by penetrating her with my fingers and frigging her to a climax, she gripped my fingers hard with her muscles and would pant hard as she came.
This could happen at any time we felt like it. Mutual sessions were the best and watching each others hands wanking like mad while semi naked was very erotic.
We also masturbated for each other, I sat on the top stair with my girlfriend at the bottom with her legs and pussy spread for me to observe while I jerked off furiously, this also took place on the sofa or kitchen table. My girlfriend liked to masturbate for me while I prepared lunch for my entertainment, pulling her labia and clit hard with her butt hole on display and wet with her juices. At the end of the weekend we were sore as hell but happy and ready to do the same again very soon.