Posted under General
Artist's English spelling found in chapter 10.
Just googled and wiki'ed and at least can add support to this as Meer Campbell is ミーア・キャンベル (Miia Kyanberu) in Japanese, so that would reinforce the usage of ミーア -> Meer. Also Johnny Vander Meer also has Meer converted to ミーア (Miia).
On the other hand though I would not be surprised if her name is derived from the Mia in Lamia (since from my understanding all the character's names in some form are derived from their monster specie's name), which I think sounds rather different than Meer. If the author just tossed ミーア into a machine translator (like on google or babelfish) it'll automatically churn out Meer as the translation. Also the Japanese wiki does also acknowledge "Miia" for ミーア and the musical Mamma Mia! uses ミーア for the Mia in the title.
Given the similarity of Centorea Shianus (セントレア・シアヌス, took awhile to find that) and the flower Centaurea cyanus (セントーレア cyanus), I had looked up the spelling of the character's name before to try and compare it with the plant's name. The genus name for the Centaurea flower in Japanese is セントーレア (Sentōrea) as opposed to her name which is セントレア (Sentorea), which is likely why the translation group translated it to Centorea as opposed to Centaurea.
Bumping to reverse the OP's alias. Seven Seas has licensed the manga and the spelling they're using for the female lead is "Miia." So the official translation for her name is "Miia" and not "Meer."
A snake-like lamia named Miia comes to live with him, and it is Kurusu’s job to take care of her and make sure she integrates into his everyday life.
It only has appeared once in the original work, that is hardly universal use in the series, which means it could also similarly as a one shot use be a mistake on the author's part.
All the monster girls so far have names based on their monster race's name. Miia can derived from "Lamia" and thus has this connection. "Meer" has no connection whatsoever to her monster race.
The other female names so you can see:
Miia (ミーア) -> Lamia (ラミア)
Suu (スー) -> Slime (スライム Suraimu)
Meroune Lorelei or for short Mero (メロ) -> Merrow (メロウ Merō) a mermaid and Lorelei is a water spirit similar mermaid.
Papi (パピ) -> Harpy (ハーピー Hāpī)
Centorea/Centaurea Shianus (セントレア・シアヌス) -> Centaur (ケンタウロス). She's named after a flower whose genus name is named after the mythological creature.
The Japanese monster spellings were taken from the Japanese home page, except for Mero who is a mermaid (人魚 Ningyo). Pronunciations taken from google translator.