KAVR-391 [VR] I borrowed my playhood friend's dick and challenged her to an extreme diet! ...But she quickly ran out of energy and her vagina was filled with pounding! A piston-like sex diet! Futaba Rena

The extreme "1cm tip air chair" is... a do-or-die muscle training method that places an erect penis directly under you to prevent you from becoming dependent on yourself. Naturally, when you run out of strength, your erect penis will penetrate and hit the back of your vagina in one go! Futaba Rena is a stoic girl who is dieting under such circumstances, but her real purpose is to have sex with you, her childhood friend! Whether true or not, the extreme squats are also true, as her thighs are full and the penis is plunging in. Since it's already inside, she has no choice but to go all the way, so she moves her muscles with all her might and shakes her hips violently!