Having just emptied her bladder into you feel her weight starting to shift, leaning to one side and then to the next shuffeling forward. Her still damp pussy passes your chin slightly moistening it all the while her anus passes your nose you get a whiff of her plans. Her weight is now almost entierly focused on your chin rather than on your cheeks as before so you need to put more effort into supporting her, nothing you can't handle though.
With her new position your view is now clear of ass and you can see up her blouse. It was one of her nicer clothing items so she might be going to a party later. You then feel muscle contractions coming from her ass and your up-blouse view is removed as she arches forward leaving you with a simple but welcome view of her asscrack. She lets go of a fart directly in your mouth giving you a entrée of the main course. It tasted surprisingly good, the Chronivac must have adapted your sense of taste to that of a toilet.
Not long after you can her your sister grunt and some appropiate muscle movements. You feel her tense up and something entering your mouth. She pushes it out for a bit and you feel it hitting your tongue and escaping down your throat. She severs the log and you feel it fall down into your throat and gets stuck a bit down. The log she just dropped was dense, no liquid shit. You bet it could stand on its own if it had the chance. Not long after she severed the first one a second one is allready on it's way down. Once again hitting the back of your thoat she severs it. This time it gets stuck further up. Good thing you are devoid of a gag reflex in this state as it hitting your pharynx would most defenitly made you gag.
After the second log there is little action, you feel her anus twitching occationally but nothing more than that. You just sit there in the moment looking at her shaven ass and a bit too short blouse. Her weight shifts again straightening out her back causing some of her hair being visible before your view enteres her blouse again. Unbeknownst to you she did this to massage her stomach a bit before once again leaning forward.
This massage apparantly did something as you feel another log decending. Once severed you could say your mouth was full of shit (hah). Your sister sighs of relif and seems satisfied. She reaches for the toiletpaper and starts with wiping from the front. As she wipes her pussy her fingers hit your chin, feeling she might have made a mess she takes the semi-soiled paper and wipes your neck as well leaving you more covered in her urine than before. She leans to the side and pushes the paper down into your mouth. Having reached for another piece she leans to the side and you see her hand decending over your eyes and entering her crack, cleaning what she can she then quickly pushes it down into your mouth. Another piece comes and she does a more thorough this time before retracting it, looking at it and pushes it down into your mouth.
Her weight distrubution now returns to normal putting even pressure on both sides of her ass, she then stands up. She haven't put on her pants or panties yet so you see her bare arse, much like you did before. She bends forward and picks up her black panties around her ankles and pulls them up and proceeds to do the same with her pants. She slowly turns around, taking out a hair tie and puts it in her mouth. looking down at you she pulls her hair into a ponytail using the hair tie. While she does this she maintains eyecontact with you but shows no emotion.
Why would she? you are a toilet. A simple object to take care of bodily waste.
Having tied her hair into a ponytail she reaches down to your face and closes your mouth. As she does you feel the shit loged in the back of your thoat going down. Your sister however, does not let go. When you have swallowed everything she opens your mouth again and looks down into your esophagus, inspecting. Tilting your head side to side she grimaced. Reaching for something behind you she pulls out a toothbrush. She does some minimal work on your teeth before jaming it down your throat and does some minimal work on your tongue. Satisfied she returns the toothbrush and closes your mouth again.
Spinning around she heads for the sink to wash her hands. While she does so you realise you cannot see your sister in the same light as before. She wipes her hands and exits, leaving you alone once again.
Who will enter next you think.