Shoujo Holic by Aoi Hana — Completed
A girl's father is relocated by his job. She's recently found the "boy of her dreams" and decides that she's staying no matter where her parents move to! She's sent to live with her grandmother and enters the same high school her mother attended. It's a religious school run by nuns. She meets a very strange girl who thinks she’s cute and shows quite an interest in her.