Uranium 🟩

Kidneys are often an issue with cats (protip is to get low salt broth/gravy and adding a small amount to the water to try and increase the amount they drink, obviously double check with the vet)

Small firm lumps normally make me think infection from a thorn, matted hair or a scratch/bite, but they elicit obviously upset reactions from cats when touched, often hissing and claws

I’m thinking kidney as you described the lump as soft, it’s roughly the right area, could even just be a kidney stone, but for the comfort and health of the cat

I saw you said you’re going to get it checked out, good luck, hope it’s nothing

Not 100% sure with cats, but I’ve had swelling and tenderness on either side of my abdomen before, which turned out to be kidneys and ureter…

Has your cat been urinating regularly? Changed frequency? Etc