レア度は「存在が珍しい」順。
プリズムホロレア：エルザ（伝説級のネクロマンサー）
ホロレア：ランたん（世界初の人工幽霊）
金レア：コル（世界的に有名だけど個体数が少ない）ピンクちゃん（先祖返りした元・人間）
銀レア：キュイ（キュイ程デカいのは珍しいけど単眼巨人自体は割と居る）
コモン：ミフィ（希少な精霊使いだけど宝の持ち腐れ）アイーナ（天才だけど普通の人間）

…番外編のネタバレ回避の為、コルに関してはぼかしてあります。ご了承をば。
ピンクちゃんは生い立ちの問題ってだけで話題すら出てこないので、ばらしちゃいますｗ

最初は戦闘力順でレア度を決めていて、コルとピンクちゃんがホロ、ランたんが金でした。
ランたんがキュイより強いのかって？強いですよ、聖幽天に変身さえできれば…ね（意味深
でも、これで進めてたらレアリティが偏り過ぎてもう…うん、変更して良かった。

Rarity is sorted by "how unusual is their existence".
Prism Hologram Rare: Elza (legendary necromancer)
Hologram Rare: Ran-tan (the world's first artificial ghost)
Gold Rare: Coru (World famous, but there are few), Pink-chan (traits resurfaced after generations, originally human)
Silver Rare: Cuey (Being as big as Cuey is rare, but there exist a good amount of one-eyed giants)
Common: Mifi (A rare spirit user, but she doesn't use her ability), Aiina (Genius, but a normal human)

...In order to avoid spoilers for the extra story, I had to be vague with Coru's. I hope you understand. Pink-chan's is only about her history, which won't be talked about, so I spoiled that lol.

At first, I was going to do rarity by combat power, and Coru and Pink-chan were hologram, and Ran-tan was gold.
Then I wonder if Ran-tan was stronger than Cuey? She is. If she was able to transform into the Heavenly Holy Ghost... (deep meaning
But if I did that, the rarity would be too biased... Yeah, I'm glad I changed it.