Just because the Maoists have won this election, it doesn't mean that the King should become a non entity. He still enjoys some support. Remember, Nepalese elections are not fought on proportional representation but on first-past-the-post system, which means a sizeable section of the populace have voted against the Maoists.
This is not to deny that the King committed grave errors. He should have held talks with the political parties and resolved to become the titular head, like in Thailand. By doing enough for the poor, he could have emulated King Bhoomibal Adulatej of Thailand, who is revered for his pro poor policies, though he is only a titular head.
That way, all this mess could have been avoided. However, the victory of Maoists is bad news for India, as they are pro-Pakistan and anti-India and will join the Chinese and Pakistanis to trouble India.