Anyway, turns out it wasn't a burn mark after all. It's this bacterial skin infection called 'I-can't-remember-what' something starts with Moisture but anyway, this morning when I gave the dogs breakfast, I noticed that ants, yes, the insects, was eating her pus. It was a lot worse than last night, so we rushed her to the vet. They had to shave almost half of her body, and it was bleeding and all the gross things you don't want to know.
She was whimpering, shaking, poor girl. The hair in her belly that was shaved off when she was spayed hasn't even fully grown yet and now she's shaved again :( There was actually 5 spots and not 3, and the doctor said that if we didn't take care of it, flies would come lay eggs there and there will be maggots in her body. Horrifying, I know.
Unfortunately, my family is gonna be away for 4 days and there's no one to take care of her, so she's now boarding in the hospital, probably whining away. Wish I could stay with her..
Good news is, it's not a very critical infection, so in about 10 days, it should be gone. They'll update as Nala & Robin as soon as we get back and thank you all for your concerns :)