@Karakui
Ooo cx Coincidences!
I don't know what I'd change it too, 'cause I'm afraid if I find a pic online it might belong to an anime I don't know, and... well, I dunno.
If you can recommend a picture, I'll switch to that.
Otherwise, I'll probably be able to find a replacement when I get back online (about 4 hours from now).
Yes, there are non-pink Mahou Shoujo MCs. Red, Nanoha and Nanoha. Just to name three. If you count spinoffs of spinoffs, there's red-green, black, the classic monochrome, and red. Symphogear's not Mahou Shoujo but orange.
I'd say go to Sankakuchan for pictures but it's very unstable today
So use Danbooru or Safebooru.
Searching via the 'Original' tag is likely to prevent you from finding pre-existing official characters
Now let's look at that applicion. Hon hon. Baguette. Thing. Bread.
If you want to call it Safaia no Kawaii just call it Sapphire no Kawaii. That's what I'd do if I were in your shoes. Or something. I don't know.
I would question if 'Eiyuu' is a legit Japanese name(which as far as I know... alright fine.) but she's pretty much immortal and can just give herself a title-like name so I'll leave it as that... I guess... thing...
To be honest, I'm not too fond of using Google Translate to churn out names. Most of the time I just choose from an existing surname, choose from a name, then combine the two for a full name.
On to the more relevant parts
I'd like a slight amount of length more to her personality.
It appears that you wish to speak to Karakui about plans. Here are some questions to fill.
1. How does she know that Kuro is coming to this educational facility?
2. Did she assume the name 'Eiyuu Aono' or did she have a different, long forgotten name?
3. Remember that she was 13 316 years ago. Take into consideration what was and was not possible back then.