The Summer of Joan B.

(from ebookjapan):
With her hands full of dreams, along with her reference books and notebooks, Joan B. Anderson is a high school student attending school. She lives with her grandfather, who works for a publishing company, and enjoys a happy life, well-liked by everyone. One day, she is approached by a girl named Barbara, who tells her that they used to be friends, but Joan B. doesn't remember Barbara... And from that day on, the darkness of Joan B.'s heart begins to peek out...

In addition to the title one-shot (Petit Flower, Summer 1980, with additional portions in Shonen Shojo SF Manga Daizenshu, July 1st, 1981), also includes:

• Boy of the Night (夜の少年, Yoru no Shounen) - Petit Flower, Fall 1981
• Stillborn Festival (水子の祭り, Mizuko no Matsuri) - Petit Flower, Fall 1982
• A Loner and One's Everyday (ひとりと一匹の日々, Hitori to Ippiki no Hibi), Grapefruit, April 1982