When Stellar Dragon King Veldanava had his daughter and lost his power, he used the majority of his remaining dragon body to create a pet dragon for her. Afterwards, he was basically left human and died shortly thereafter because [The Voice of the World] set up a scenario for his and his wife’s demise due to Its believing that he, as the Supreme Creator of the Universe, betrayed the world and its creatures by no longer loving them all equally after falling in love and marrying a human woman, fathering a child with her, and losing his Powers of Divinity to his daughter. Since Rimuru ends up with the same status, as a Transcendental God in charge of the Universe, if he fell in love with any of his “children,” (the girls) more than the rest, and sacrificed his power to have a child, he’d be treated to the same demise scenario.