Silver marshaled himself internally. The mares wanted a strong and able prince, and he had to be one anyway if he was going to be useful during this journey. They both wanted him, but they had a lot of social caveats hanging off of it. Just stay cool... He entered the room to find a scowling Shei glaring at him. "You promised! You gave your word! It was the only request I had." She stomped a hoof angrily on the floor. "I thought you were better than that!"
Silver stepped towards her, letting his magic flow down into his legs to keep them steady and sure. "I have decided to keep your sister forever. I took her in all ways, not in any idle gesture, but to claim her entirely."
Shei's expression went from rage to embarrassment like a light switch. "W-what? You..." She recoiled a little, looking lost. "You're taking her as a wife? That is very improper. We are commoners, and you are a noble. You're taunting me, and hurting her! Don't speak impossible things!"
Silver raised a hoof, lifting Shei's face towards himself. "I meant every word I said. She is not my wife, but she is mine, forever. She is free to seek out a companion, but they will need to know that I own her first and truly."
Shei's flush grew deeper as she trembled. "Y-you did... You've taken her as a concubine?"
Silver smiled. "As I plan to take you, when your time comes. Did Celestia not mention my task? I have a race to sire, and you, my lovely mares, will bear some of them. I will never abandon you. If you don't believe it out of my kindness, then simple utility. I need broodmares, and you can do that and much more beside."
Aila approached suddenly. "What is this? A new race? You're not just a lustful stud?"
Shei sank to her haunches, her anger melting in confusion. Was being commanded to help brood a new race an honor? "Please, what race, as my sister asks."
Silver inclined an ear towards them. "I am a lunar prince. There are only lunar pegasi in Equestria, a matter I intend to address at behest of my own progenitor, Luna. Any foal I sire is very likely to be a lunar pony themselves, probably of unicorn descent. Even those that aren't have the potential to make them in their own foals."
Aila looked over to Celestia, who sat so calmly on her bed. "Is he weaving wild tales?"
Celestia shook her head. "Everything he has said is truth. He is the only alicorn prince, and the only lunar royalty of any kind."
Shei took a wavering breath. "This... this changes things..." She frowned at Silver. "I am still angry you didn't... didn't warn me... You promised."
Silver smiled at Shei. "I must do what is right at the moment. That is part of being royal. I did what was right at the time. If Aila feels I have done her wrong, she should tell me." Silver looked at Aila. "I have bred you, and I will do so again. Does this displease you?"
Aila darkened, shuffling at the floor, suddenly uncertain in the face of the more-confident prince. "I will fight you."
Silver leaned towards her. "And I will win, but you will enjoy the battle."
Shei gasped loudly. "Sister! You're... You want to fight him?"
Aila grunted softly. "I will not be taken quietly! If I'm so worthy as he claims, he can prove it." She turned up her snout.
Silver nodded. "I will prove my love for you every time, if I must. You are a mare worth fighting for. However..." He lifted a hoof. "There should be rules to polite combat. I will share with you the safeword I have with Celestia. If either of us says 'Nova', and we stop. No questions. No punishments. I will conquer you, but I will not pillage you."
Shei perked an ear, the entire thing seeming to confuse her, but Aila seemed pleased. "You will find the next time I will be better prepared for you, my prince. I won't have need for the feeble defense of your words, but it's kind to offer it." She turned away and walked off, seemingly done with the conversation.
Shei pointed at Silver. "What did you do to my sister?"
Silver leaned in to nuzzle at Shei, and got softly bitten for his trouble. He rubbed his nose lightly. "I came to an understanding. She doesn't want gentle romance. She wants the company of someone able and willing to best her."
Shei shook her head. "I... don't want that."
Silver smiled softly as he sat up. "I don't expect you two to want the same things, sisters or not. For you I would have a much gentler romance. When our business concludes here, we will have to do something... special."
Shei gave a mute nod, her anger entirely broken by the unexpected twists and turns. "May I also use the word?"
Silver tilted his head. "I hope you never feel the need to use it, but, yes." He reached for her, and she let him draw her close. He gently kissed a cheek. "I may own you, but it is not a blind ownership. Tell me if something is on your mind. It reflects poorly on me to abuse my possessions, and does not sit well with me as a pony."
Shei slipped away and joined Aila, speaking softly with her. Silver approached Celestia. "Was that what you were hoping for?"
Celestia smiled her serene smile. "Well handled. Now, about Amenti. As you were told, funding will soon become an issue, and in this I can offer some assistance. Not for free, of course. That's a terrible precedent, and looks poorly. The city provides an important waypoint between Equestria and the region. Cleaning up the port would make a lot of lives easier for my ponies who do trade in the area. I could easily justify assisting with this, but simply offering the money would invite prying eyes. What is your suggestion?"
Silver perked his ears. "I'm certain you would know better than I... What if she... made a fee to the home country of traders?"
Celestia nodded lightly. "That might raise revenues, but strain her relations with the same countries. I would pay, but I doubt she's had contact with the other countries it would affect to clear this."
Silver tapped his chin softly. "Then what about... a fee on the individual trader, with a caveat that their country can pay all at once for everyone, if they want to? The money being specifically reserved for maintenance and upkeep of the city?"
Celestia smiled gently. "A modest fee would get some grumbling, but is unlikely to create too much stir, especially if there is quick and immediate results from the money. Go further."
Silver raised a hoof. "Do you know if that builder's guild also works with boats?"
"They do."
Silver smiled. "Then she should charge more, but include ship repairs and upkeep. That would win her a permanent ally with that guild and its members, right? And make the harbor a tempting place to be if the price is reasonable."
Celestia rolled a hoof. "I trust you will inform her of this plan then."
Silver blinked, then clopped his hooves together. "Oh! Right. I'll do that tonight. Maybe she'll already have the idea in mind."
"She may." Celestia leaned in and bumped nose-to-nose. "I trust you will relieve your frustrations in the future on the Windsongs now that you have won them."
Silver tilted his head lightly. "Does that mean you don't--"
Celestia frowned delicately. "We have a date. Prepare yourself."
Silver deflated a little, but nodded. "Of course."
When night came, Silver slipped off into the dreamworld, thinking first of Luna. Nothing happened at first, until Luna emerged from down the hallway, approaching him at a light trot. "Good day, Silver Stars. Pray tell how your venture goes?"
Silver smiled at her and advanced, rubbing snouts gently. "Good to see you, Luna. I... need your help. I've put my hoof right in a mess, and you're likely the only one that can make this better while I'm away."
Luna perked an ear, then a sly grin overtook her expression. "Does your herd expand further?"
Silver tensed a moment. "Sort of... I have two servants slash slaves slash concubines. I already quickened one of them."
Luna nodded lightly. "And I gather you intend to bring them home? Slavery... I thought that had faded from the world while I was away. Not very economically sound, Tia has told me, and morally ugly."
Silver made a wide gesture. "Different part of the world, different rules. Can you break it to my wives... gently? I think Fast Change will be fine with it, provided she gets a chance at them, and I doubt Twilight will... fully grasp it, but Night Watch I worry about. She trusts you, and loves you."
Luna held up a hoof. "It was at my command that you stud. I will not fail you in this, Silver. I will ensure you have a home to return to." She flashed a smile. "I know just the way to soften her heart to the idea. By the time I'm through, she'll think it was her idea."
Silver blinked. "Don't brainwash her!"
Luna snorted softly. "I'm not making her forget anything, but I am the mistress of dreams. She will be ready for them, of this I promise." She vanished from sight, leaving Silver alone.
Silver grunted softly, hoping Luna would use soft touches, not crude manipulation. Silver turned his thoughts to Amenti, and slipped into her dreams, shrouded from sight. He found himself, another himself, standing over her, Celestia just beside. Both alicorns were easily twice her size instead of their about half over again actual size. Amenti sat in front of them, looking unsure and fearful.
Dream Celestia shook her head. "You can't have him. He's mine!" She extended a wing that grew large enough to conceal Dream Silver from view. "I do not share my toys."
Silver frowned a little. The dream wasn't productive, and a little creepy by his view. With a wave of a hoof, he banished Dream Celestia from sight, then slipped into Dream Silver, assuming his role in the dream. "Hello, Pharaoh."
Amenti smiled brightly, accepting that Celestia was simply gone in a fit of dream logic. "My prince! Will you guard me? Or are felines too alien to interest you?"
Silver perked an ear. As a former human, the entire thing tickled him. Felines were no more or less alien than ponies, though he had grown quite used to ponies. "I have an idea for you, but it is a little thing. You've probably already thought it up." Silver shared the idea of a small fee to docking that would go towards city repairs and ship upkeep, and giving the contract to the builder's guild that Amenti was already making solid progress in winning over. "Celestia may seem distant, but if you give her the option to pay in the sake of her ponies, well, she values them greatly, and she will gladly pay an entire year of dock fees to spare them."
Amenti smiled brightly. "I will consider your words, my prince. Now come, let us retire. The court is no place to discuss certain things." She rose to her paws, and Silver slipped away, leaving his dream self behind to indulge Amenti in whatever manner she had in mind. A smart part of him worried that she was having such thoughts, but most of him was just glad he got the idea out and message delivered.