Should start out by giving a Fare warning of scat/watersports/guro porn in these things stories. For someone not really into scat the great make up is the unaware suffering and helplessness 

Stories: 

1. A man hidden under a trailer as a kinky fetish with one woman he meets ends up with him getting used by 4 unawarely teens having a sleep over which he fed the night before (low-scat)- https://www.literotica.com/s/fantasy-overload-pt-01

2.Man agrees to become a toilet of a woman and is sealed hidden under the floor and tollet.He spends many years there and through a newyears party with unaware people using him until he meets his end after the hous was sold to a single woman and her two teenage daughters killing him after some time (Scat/watersports/guro) - https://www.mistressdestiny.com/threads/the-permanent-objectified-human-toilet.400933/ 

https://www.furaffinity.net/view/30216976/ 

https://www.mistressdestiny.com/threads/sisters-new-toilet.415319/page-6 

http://thefartcloset.com/others/-jimmysnewlife.html 

https://www.mistressdestiny.com/threads/army-hijinks-part-1.433370/ 

https://www.mistressdestiny.com/threads/ibz-in-the-sewage-pipe.394178/ 

https://metalbondnyc.com/in-the-drum/