Ive had 4, actually. Two were siblings.
FORGET TRYING TO TAKE CARE OF THIS NATURALLY UNLESS YOU WANT TO MURDER YOUR CAT. Full stop.
Its not a joke, and it quickly kills male cats. They can be fine one day, practically passed out and dying the next. You have to keep them hydrated and eating the right stuff, avoid dehydration from heat or other causes, treat UTIs fast, and monitor them for signs of trouble.
Yes, you will need to not free-feed, and segregate who eats what. The good news is that once its under control with proper vet care, which can happen in just a few weeks if you follow recommendations, it may stay away for years at a time. With one kitty, it was a medical emergency once, and it required a major intervention, and he remained good the next 17 years or so. With a couple others - the siblings we have now - it flares up occasionally, but not badly. Its super hot now, and that seemed to be the precipitating factor. But otherwise, theyre good, they eat the prescription diet and like it, and being watchful tells us as soon as they are straining g or pee inappropriately as warning signs.
Not joking - talk to a vet about any rescue groups that will foster him and rehome him as a precious special needs kitty with experienced folks, if you want to play around with trying something natural.