Identity
When they had first met, she had introduced herself with confidence. The rainbow that flowed from her wand and arched over her head was instant, and she knew exactly who and what she was.
She was a butterfly. She was a magical princess. She was Star Butterfly, a free spirit.
She isn't so sure after that. Her family had stolen the Butterfly name from another more deserving. The crown of mewni had been tossed away from the rightful heir and into the crib of her great great something grandmother. She wasn't magical anymore. There was no mewni to be a princess of (and if there were it would've stayed with Eclipsa and Meteora). Could she even call herself a Butterfly?
She didn't say any of this to Marco, but he seemed to just know (he always did). He knew from the way she changed her introduction ("Hi there, I'm Star!) and how whenever a form asked for her last same she seemed to pause just a moment and bite her lip before continuing. He just knew.
Marco did what he could without coming out and saying it, as he knew how she would run if he did. That wasn't much though, and every time she looked unsure of himself he clenched his fists and hated that he couldn't do anything.
It got better over the years, but sometimes she would still get that familiar pang in her chest when someone asked where she got such a peculiar name (those from Earth still hadn't adjusted to the Mewmans completely) or one of her old subjects that hadn't hated her calling her princess Butterfly (those from Mewni still hadn't adjusted to Earth completely). It didn't help that she didn't have any other name to go by.
Or at least, she hadn't, not before Marco gave her one.
That hadn't exactly been his intention when he asked her to marry him, but it was a plus nonetheless.
She could be Star Diaz. A name not stolen, but freely given. She would be welcomed into the Diaz' as one who had earned her place, and she'd know who she was.
As soon as it had been made official, she would introduce herself with just as much, if not more, confidence as she used to (albeit in a less magical and more mature manor). Marco smiled every time he heard her.
She would fill out paperwork and always smile when asked for her name, and no one asked her about her last name anymore (and when someone that used to know her called her a Butterfly, she never winced. Only smiled and corrected them).
A/N: Short I know, but it's my first (and likely only ever) Star Vs. the Forces of Evil Book. I just figured that an identity crisis was in order, and a simple solution presented itself to me soon afterwards.
-Lucas_Gilbert