こちら、幸福安心委員会です。 (Kochira, Koufuku Anshin Iinkai desu.)

Background
The lyrics tell everyone that being happy is their duty, and that the Happiness and Peace of Mind committee will support them. 'Its your duty!' is repeated throughout the song. Miku appears to be the spokesperson for the Committee, forcing their citizens to pretend to smile and be happy. Anyone who fails to comply is executed, you can hear roaring brainwashed crowds behind Miku. The song's tone changes dramatically at the beginning and end to sing the truth of how people feel.

The lyrics mention 'Undine/Ondine', a creature that is a water elemental/water nymph of Greek and German legend. In the myths they sing with beautiful voices, and seek to marry a human to gain a soul. However in some stories those who are unfaithful to an undine are cursed with death. This appears to have been the fate of the knight in the song. Miku may represent an Ondine.