All of Twilight's friends have passed away, but as the immortal Princess of Friendship, Twilight found she could still see their spirits. This proved not to be the boon she expected, as their spirits would move on shortly after... with the exception of her love, Rarity. Still, her time was inevitably coming, and Twilight worked to discover a way to keep her around forever.
She succeeded. It came at a cost, but Twilight found that she was more than willing to pay it.
First of two unrelated Halloween stories this year, and also part of the 2024 RariTwi Bomb.