The Fairy Princess Servants Game Over is an ending which occurs if the party loses to Princess Anathema IV in the Fey Mansion. An altered version of the ending with additional dialogue can be obtained if during the fight Eric(a) is the last Cutie Knight standing, Princess Anathema is below 25% HP, and the player accepts her offer to surrender.
Having fallen in battle (or possibly surrendered in Eric(a)'s case), the Cutie Knights have now all been transformed in body and mind into Fairy servants obedient to Anathema's will. Finding her new servants more favourable to the group of pathetic Fey Heralds arriving late to the scene of the fight, Anathema quickly has them swear loyalty to her - a process completing their transformation in mind and soul that wipes away any traces of rebellion... although their personalities seem to remain at least partly intact.
Pleased as she is with her new servants, Princess Anathema is also not one to let go of slights and promptly brings her new entourage to the dungeons for their punishment for their previous assault on her person. She quickly shows her sadism in administering physical punishments to the Cutie Knights, though with their new bond to her they also find pleasure in fulfilling their Lady's orders and her satisfaction in hurting them.
After having satisfied herself with their punishment, Princess Anathema next puts them to the test with an actual assignment. At this point, under the conditions of the alternate ending scene having Anathema be impressed with Eric(a), she will designate them as her new second in command and the leader for this mission. Otherwise, the Cutie Knights are simply sent off.
The mission, as it turns out, is to kidnap Nele who is out on a recruitment mission for a new Magical Girl. Understandably shocked by the reappearance of the missing Cutie Knights in their new forms, Nele is rather flustered and then quickly knocked out and secured by Veronica. In the normal scene, the prospective Magical Girl will leave at this point, but a leader Eric(a) will take the initiative to kidnap and bring her to the princess as well.
Adjusting to their new lives as Fairies, the former Cutie Knights become powerful enforcers to Princess Anathema, serving her will with utmost dedication. In the alternate ending they take this even further: the Magical Girl Eric(a) took back is to be only the first of many. Under her reasoning, Magicos are still a threat; one which Magical Girls are particularly effective against... and since Magical Girls are only effective thanks to Fairies, should it not be the Fairies calling the shots? And so it comes that, with an entire army of enslaved new Magical Girls under her command, Eric(a) would rise as one of Princess Anathema's most trusted advisors, guiding her soldiers to victory after victory.