Mayonaka No Ariadone

One day someone transfers into WATAYA Chiyoko's school. His name is KYUUGA Chiharu-kun. They used to be childhood friends, but he was always mean to her. She remembers him, but Chiharu-kun doesn't seem to recognize her. While following him to return something he left behind, she gets mistaken for someone that works in a very odd club...
By StarryHeaven:
Supernova Shimotsuki Kayoko’s new-age romantic suspense.
When you have worries, is it about whether or not you are short or about your new class? Those were the problems that normal high school student, Chiyoko, faced. However, one day she meets her childhood friend Chiharu and Chiyoko’s world changed. But when Chiyoko stumbles her way into a secret underground high class club, she is surprised to find the truth…