You decide that you would like to take a closer look, up close and personal at that ass she is hiding. You climb up the bed trimming and the mattress and reach the top of her bed. You see to your delight that Lucy is sleeping on her belly, makes things easier for you. The bad news is that she was still wearing her bikini, which meant that you cannot observe and enjoy her booty from outside.
You start your journey by climbing up her feet, and walk all the way up her leg, thigh, until you reach the rising hill of her left butt cheek. You grab the fabric of her bikini bottom and start climbing, it takes you a few minutes to reach the top, after that you stand on the top of her left ass cheek and observe. Her covered ass looks fantastic at this size. But you are still looking at her pantie, you still need to take a closer look. Looking around you see that the top of the swimsuit doesn't reach all the way up her ass, it looks like they are a bit loose, she obviously has not pulled them all the way up, you walk until you reach the underside of her back. Now you are looking at the beginning of her ass crack. You decide that it is time to check out the prize, crawling on four, you slip between her butt cheeks and the pantie, after going inside you can stand now. It is darker here because the fabric blocks the light, but you can still see the valley of her ass. You start walking a bit inside as her butt cheeks rise above you, you push your way forward as her cheeks surround you. It is completely dark and you cannot see, you start thinking that you are going too far.You put both hands and legs on opposite sides, pressing against her butt cheeks and start climbing up. You emerge on top of the cleavage of her ass cheeks, you stand up carefully, the fabric of her swimsuit underwear above your head and her butt cheeks around you. You stay here for a few minutes, admiring the ass in front of you.
Suddenly you feel the ground moving and separating! Actually it is not the ground it is Lucy's Ass cheeks parting, she is shifting her position while sleeping and the movement of her legs causes her ass cheeks to part. You suddenly start falling. Her butt cheeks close on you, engulfing you. You start struggling to maintain a hold and not slip too far in. Using both hands and legs to push against the ass cheeks of Lucy's ass, you feel that you have finally got a hold and not slipping down, but it is very hot in here. The pressure down here is more than it is up at the start of her ass crack, you are now deeper than you wanted to be and her ass cheeks were pressing on you from all sides, you can apply enough pressure with your hands and legs to keep from slipping down however you are not sure you can climb up. To make things worth, your sister's ass is hot in here, and not just sexy hot, her buttcheeks are radiating heat, you can feel all this heat and to your horror you realize that in no time you will be sweating, and loose your grip. Soon you will start slipping again.
Your hands and legs are finally too wet for you to maintain a hold, as you start slipping again your struggles become more desperate, you cannot believe that the marvelous ass you were enjoying five minutes ago, is now absorbing you deeper and deeper. You cannot see anything and you cannot smell anything because the space is very compressed, but you know you are very deep in Lucy's ass and you need to do something unless you want to end up sleeping inside her asshole, which couldn't be very far from where you are.
Suddenly you feel movement again. The ass was moving, or rather.. rotating. It only lasts for a few seconds, and you are disorientated for a bit, then you realize that Lucy probably turned around, now on her back, this becomes obvious as suddenly the pressure increases on you as the flesh of her ass cheeks come squeezing on you. You can barely use your hands and legs to keep them from crushing you, at least you are not slipping inside now. But you cannot climb outside like this. You cannot believe that your busty sister is sleeping not knowing her hot ass is squeezing the life out of you. You are not even sure what the watch will do in this situation, if you give in and gets crushed inside your sister's booty, the watch might as well energize you in the same place, just to get crushed again.
Then for the third time, you feel sudden movement.