Hivemind Control

Twilight waved as Luna's carriage rolled back toward the Equestrian border. Her progress had been swift, and after a few days with no vaginal sex, she'd stopped laying changeling eggs temporarily. She was now able to don a disguise as herself, and as soon as she had a designated egg chamber, she could start laying changeling eggs with her two changeling handlers.

Twilight was coming along nicely, herself. Her shoulders and hips had already been eaten away, and her wings and back were next. Cercus had even taught her a little bit about transformation, and she was almost able to change the colour of her hooves, though she was still unable to hide the holes, and she certainly wasn't ready to make them feel like real hooves yet.

Still, progress was progress, and with a command from Cercus not to pass beyond the gate, she was allowed to watch as Luna was carted off. If she arrived safely and nopony suspected a thing, Cadance would be sent back to the Crystal Empire in less than a week.

Speaking of Cadance, she looked just the way she used to, and was still as as lusty as ever. Of course, she was not allowed to undergo the same treatment Twilight was, as her love was legendary, and could potentially overpower the entire hive if left in her own care. She was especially not allowed to see Shining, as the two of them together would undoubtedly spell the end of this incursion, and potentially eliminate all of the control the changelings had accrued in the process. Underestimating them in the past had led to the changelings' defeat, and that's not a mistake they would make twice.

Twilight returned to her room. When she left for Ponyville, she definitely wouldn't miss this place. While she had come to appreciate the sturdy, yet lightweight structure and soft, easily sustainable lighting, it was dull, dull, dull. She'd mentioned several times that Cercus should decorate, and he had hung up a poor excuse for a painting, but returning to her castle in Ponyville would be a spectacular lift to her mood. Not to mention the feeling of the wind, the taste of freshly-picked apples and of course the warm greetings of happy ponies.

Almost. It would happen soon. Cercus had given his word, and he'd kept most of his promises already. Taking her back to Ponyville with some of her friends would be a breeze. She just had to wait a little longer.

She did not have to wait long for his arrival, however. He walked in with a big smile on his face, but it melted into shock when he saw her on the bed. "What are you doing here?" he asked. "I thought you wanted to see Princess Luna off?"

"She left a little early," replied Twilight. "She looked spot-on. You trained her well."

"It wasn't me."

"You as in you collectively. The changelings in general."

Cercus smirked. "I know what you meant. I was just fucking with you. Speaking of which..." Twilight opened her mouth and stuck out her tongue, but Cercus shook his head. "Mount the bed and spread your legs."

Twilight's eyes shot open as her hooves pulled against her. "You said not until I was ready!"

"It's not that, calm down," assured Cercus. "You've been on the treatment for two weeks. Your body is slowly acclimating as time goes by. You look to be past the point where you should be following orders to the letter, so let's see how well you perform. Spread those lips."

As Twilight's shoulders hit the bed, she found herself unable to stop her front hooves from reaching back and pulling apart her flesh, as if inviting him in. "Please, no..."

"Now beg me to fill you."

Twilight's jaw forced itself open, and the words she'd been dreading for the longest time escaped her lips. "P-please, Cercus... Fertilize my eggs..."

Cercus smiled and placed his hooves on Twilight's flank. "Call me Dominus."

"F-fuck my p-p-pussy, Dominus. Please..." she sobbed.

"Well, since you need it so badly... No."

Twilight looked back at him. He was rock-hard, and looked like he was about to push his way into her, but he wasn't going to. "Wh--" Twilight was shocked. "What?"

"That doesn't count as real begging; I ordered you to do it. Besides, this was just a test. I needed to see how far you would go against your will. You should be to the point where you follow my instructions without hesitation, and here you are, spreading your pussy and begging me to fuck you as I commanded. Now, let's see..."

"I can't believe you wou--"

"Be silent."

Twilight shut her mouth. She couldn't even grunt through her nose. She was definitely feeling the effects of having given over her freewill. This was terrifying.

"Be calm."

She took a deep breath. This was, after all, just a test. He hadn't broken his promise after all, he'd just frightened her a bit in trying to see how far she'd come. She hoped he was pleased with how well she was performing.

"Be glad."

It wasn't so bad, after all. Of course he'd be pleased with her. Why wouldn't he? She'd performed admirably, and there was no way he was disappointed in her.

"Feel your emotions as you naturally would. You may also speak, but no yelling."

Twilight's distress came rushing back, but now she was ready for it. "Why would you do that?" she whinged. "That was terrifying."

"I had to give you commands you really didn't want to do," answered Cercus. "It had to be something you would actively fight against. If I told you to suck me off, for example, you were going to do that, anyway. You could mock fighting back. If I'm being unreasonable, though, you would push against it, and that's what I needed to see. You of all ponies should know how important it is to collect accurate data with blind tests."

Twilight's jaw dropped. The more she thought about it, the more she knew he was right, and despite how small she felt when she lost control of her actions, she had known for weeks that something like this could happen. That's what this process was all about, after all. This had to happen for her return to Ponyville. Of course they wouldn't let her tell all of Equestria about what the changelings were going to do. They were going to demand that she act as if everything was alright. It would be stupid of them to return her to Ponyville with no way of keeping her from talking.

"Play with yourself," commanded Cercus as his now-lubricated cock worked its way up her arse. She did as she was told, still trying to come to terms with her new situation. It wasn't just her, either. Rarity and Rainbow would have to go through the same test, or at least something similar, if they were going to be going back to Ponyville. She could only imagine what kind of horror awaited them.