Steal My Throne? My Three Dragon Kings Return for Me

I am the only Dragon Queen, courted by three powerful Kings. After an attack leaves me in a coma, my servant claims they betrayed me, so I make him my consort. Three years later, I catch him with his pregnant mistress and learn he's poisoning me, plotting to burn my golden egg and steal my throne. He thinks I'm powerless. But my egg cannot burn, and the three Kings he kept from me have received my letters.