How does the North Korean constitution's promise of democratic processes match with reality?

The Democratic People's Republic of Korea, best known as North Korea is constitutionally a representative democracy, or a republic that allows all people the right to vote, aged 17 and up. It has a national legislature called the Supreme People's Assembly whose members are elected every four to five years. Almost 99 percent of people attend the polls in time for the elections and, interestingly enough, contrary to popular belief the ruling party Workers' Party of Korea currently has a majority of 87,5 percent of the seats whereas the rest of the seats are distributed among representatives of three other political parties. Although the elections are secret which could allow for free elections, the reality is that elections are held only for show, as neither opposition nor freedom of political participation exists in North Korea.