If you liked the Letter Bee TV anime, the Anime-Planet community thinks you'd like:
The fantasy world of Arcadia is in peril: fierce monsters known as Thanatos are sucking the life from humans, and only men known as Purifiers can vanquish them. Angelique is a young girl who attends Melrose Girls Academy and thought her life was normal, until the dashing Nyx told her that she has hidden powers within. After a brutal attack by a Thanatos, Angelique finds she is able to help in the battle and heal those who have been sucked dry; her powers are real, and she discovers she is in fact the Queen's Egg - the only female Purifier. With the help of allies such as shoot-em-up Rayne, the happy traveler J.D. and Silver Knight Hyuga, Angelique will learn about her powers and help put a stop to the Thanatos.
Both are about a character who is learning about their new powers. The settings are both fantastical worlds ruled by a queen who is worshipped, and the character has to fight evil monsters in order to protect the people they love.