Serious question about managing human waste with no toilet

cheapest easiest is sawdust.

dries out the stool and removes odour.. also there are natural active germ killers in the wood itself.

look up bucket toilet system as one example.

Can you call septic pumping business and clean your septic out. Or do you not have any toilet at all?

My grandpa, would run a line outside, to a hole, about 4' x 4' x 4' deep. Cover it with corrugated sheet metal. Like for a roof barn. It didn't smell. He'd also run the washer and sink into the garden. This was a common type used for a long time. Depends on where you live if you can get away with it or not.
One place in California had a bunch of cabins, an inn. All their cabins were setup that way. But they were covered in big wooden construction. Almost like a deck would be made out of wood.

Cheers!

just make sure you have hemostatic gauze for a ripped asshole.

Aim your dumps out the window OP or sweep them under the door