I hissed at him mostly when I first got him as a foster home. He had lots of bad habits since he lived on the streets for so long. He broke those habits quickly and we have been a "hissless" home since. Sometimes we understood one another without words - he kept peeing behind a wall on the floor, I put the litterbox there and he knew what to do next.

He was so spooked initially he didn't eat for a month and hid under the sofa. What got him out was me watching a female cat that was peeking out of her carrier and meowing at the camera (almost playing peekaboo). Though to be fair, he was exploring at night - I caught him doing it next morning when I saw pawprints on a dusty shelf, like 10cm away from my head when I was sleeping. He just didn't eat anything (wetfood, egg yolk, dry food) which is scary when a cat does that, they need to eat each day or they get liver issues. Pheromones weren't working. Vet said he needs exposure therapy which meant back to a cage with him. Spent hours sitting next to him watching either bird videos or some series / cartoons I was watching at the time. He still runs at the slightest rustle but he has chilled out immensly, became a complete and utter lapcat, and knows how to use voice buttons to say what he needs. My latest trick with him is asking him to turn off the lights. There are two outcomes, either he goes and turns them off, or he gets up, presses the "no" button and goes back to sleep / whatever he was doing. Both outcomes are hilarious obviously