You gently raise her feet and slowly start to suck on them, tasting the chocolate mixed in with her natural sweet taste. You swallow more of her making sure to lick her every part as the she is a very tasty meal.
With a few final gulps you close your mouth sending her down to stew in your stomach, still sleeping from the sugar she ingested
"Buuuuuurp, damn she was tasty" you look down at your enlarged stomach full of packed meat ready to digest. Your sister is still sleeping soundly unaware of her future fate as a dump and body fat.
You walk up the stairs having finished cleaning up and with a meal in your stomach, you decide to finish digesting over night.
Changing into your nightwear, you still rub your belly enjoying the sounds of its churning and letting it lull you to sleep.
Overnight your stomach works hard, reducing your sisters body to nutrients and slop to be pumped into your intestines
and eventually pad your body as soft fat. Eventually her body is completely turned to soup.
Slowly your stomach shrinks one by one and your ass and thighs grow larger. whatever your body couldn't use, is collected at the bottom waiting to be disposed of
The next morning:
You wake up to a poking feeling around your stomach. You look to see your brother poking your pot belly having gotten rid of its occupant.
"mmhm, what do you want" you say sleepily as you have yet to fully wake up.
"Mom told me to come wake you up, also we cant seem to find sister anywhere. Do you know where she went?" he ask not knowing that he is touching what's left of her.
"No, also 5 more minutes" you say that as you cover your head with the blanket. Suddenly you feel a pressure in your bowels begging for release.
"Actually never mind" you say that as you quickly head to the bathroom to release its guest. A few farts erupt as you make it over.
As you make it on to the toilet, you start to push your sister back out, her form now much more soft and flexible.
At first, a few farts make their way out as the first log starts to emerge stretching your ass nicely on its way out as it plops onto the toilet below. The feeling of her slowly sliding from between the ass cheecks she is now a part of makes you extremely horny and you start to slowly masturbate to the rhythm of her sliding out.
A few thicker turds follow as more of the indigestible parts of her start to leave with a shards of bones mixed into the shit pile, the only evidence this crap was ever a person. After 10 minutes of shitting the logs she made, her skull finally pops out sinking into the pile marking her final exit. With that you finally orgasm making sure to glaze her remains with your cum.
"f-fuck sis, you were designed to be a perfect turd weren't you?" you say panting as the orgasmic feeling subsides.
As you get up from the toilet you look down at your former sister and laugh at how much better she looks clinging onto your ass as beautiful padding as you play with your newly acquired assets.
You decided to flush her remains down before she stinks up the place. After that you decide to...