Meido, Mei

Mei has dark hair that is styled neatly and held back by a white veil. She is usually smiling, has her eyes closed, and is almost always seen in her maid uniform.

Mei is polite and proper, rarely showing strong emotions. She is very loyal to Hahari above all else and is unlikely to do anything unless given permission or ordered to by Hahari specifically. Mei's fanatical loyalty to the Rentarou Family and the Hanazono Household results in her gladly offering to "eliminate" people that threaten, insult, or even mildly inconvenience Rentarou, Hahari, or the other girlfriends.

[Spoiler] She is Aijou Rentarou's 8th girlfriend. Even after falling in love with Rentarou she still holds Hahari at the highest regard.

Although rarely seen, her eyes are rainbow-colored. [/Spoiler]

Name/Birthday Pun Explanation:

Meido (銘戸) is a homophone for "maid" (メイド) (meido).

Mei's birthday is on May 10th. This is a pun on Meido, "Mei" being "May" and "do" being Goroawase (wordplay) for the number 10.

(Source: 100Kanojo Wiki, edited)