Twilight flicked agitatedly through her book, not even recognizing the words on the pages. It had been hard enough to act "natural" around Celestia, but it would be difficult (possibly even worse) to act so around Spike. Thinking about him caused her tense and hardened face to soften somewhat, and the pages of the book turned less violently.
Spike...
It had not been easy for him either, all those lonely years. He had been good to her, exclusively loyal to her alone after he went berserk... She remembered the days, months, years she had spent visiting him in his horde at the Everfree Castle, where he guarded the Tree of Harmony on her command. Only her visits broke through his feral mind, and she felt a cold wave of guilt fall over her, though, when she realized that in the future, he was all alone, as she had came back to her old life. He did not deserve just a fate, and she shuddered to think what he could do if she suddenly disappeared without a trace...
"Hey Twilight?"
Twilight snapped out of her thoughts with a startled cry, her wings fluffed out, and her horn glowing, ready to cast some sort of offensive spell. She calmed down, however, once she saw Spike standing in front of her, a slightly worried look on his face.
"You looked kinda sad, so I was wondering what was wrong?"
Twilight just stared at him. She thought over the ways she had neglected him during this state, however minor they had been. Making him sleep in a basket for a full year; not ever telling Rarity to stop abusing his crush on her; not destroying his jealousy when she had adopted Owlowiscious; or making him stay up late with her to reshelve books purely for her own pleasure. Tears came to her eyes, and she embraced him, her wings covering him like a blanket.
"T-Twilight??" Spike exclaimed, startled. "What's wrong?"
Twilight began to cry freely. "I'm so sorry, Spike..."
Spike reluctantly pushed away from Twilight, and looked at her with great concern. "For what?" He suddenly looked fearful. "If I did anything, I'm so sor-"
Twilight held up a hoof to silence him. "I haven't been a good mother to you all these years. There have been times where I've treated you horrendously, as if you could be replaced by another assistant." She stretched out a wing, inviting him into another embrace.
"M-mother?!" Spike yelped.
Twilight giggled. "Well, I did hatch you, didn't I?"
"Oh right," said Spike sheepishly. "I never really thought about it that way..." He looked at Twilight's inviting stance, and accepted the hug. "Does that mean I have to call you 'Mom' now?"
Twilight chuckled. "Only if you want to, Spike." She hugged Spike just a smidge tighter, but soon released him. "It's getting late, Spike. You should go to bed." She suddenly started. "That reminds me! There's only a basket for you to sleep in upstairs." She smiled apologetically. "Do you mind sleeping in it just for tonight? I promise that we'll go out together tomorrow to buy you a proper bed."
Spike nodded excitedly. "Sure thing, Twi! Good night!" He started up the stairs, but then turned around to look back at Twilight. "By the way, I'm sorry I interrupted you while you were reading that book. You were so absorbed in it! It must have been really good. What is it?"
Twilight smiled, blushing a bit, and looked at the cover of the book. It was a good thing that her back was to Spike; he would have seen all of the happiness and warmth drain from her, replaced by a cold distaste. She resisted the urge to scream, throw the book, and incinerate it. She was also fortunate that Spike noticed nothing amiss in her voice as she answered him.
"It's 'The Life of Our Glorious Celestia', as written by the Order of Sol Invictus."