Skip Beat! is a shojo manga by Nakamura Yoshiki, whose other works include Tokyo Crazy Paradise, which I adored. Currently there are 116 chapters scanlated and 10 volumes translated into English by Viz Media.

Kyoko came to Tokyo to support her childhood friend and the center of her universe, Fuwa Sho, as he climbs to the top in showbiz. Lately he hasn't been coming home much, though, and when she learns that he brought her along only to work for him, she snaps completely. Her dark self runs rampant, making up for lost time, and she acquires some adorable-but-terrifying demons along with her new super-developed negative aura. She decides to go into showbiz herself to get revenge on Sho by outshining him, and tries to join LME Productions, the agency of Sho's rival for the hearts of Japan's female population, Tsuruga Ren, who promptly throws her out. Her journey to the top begins at the bottom, as she has to fight her way even to join an agency! And it doesn't get easier from there. Ren is out to get her, girls seem to hate her, she breaks her ankle, and everyone laughs at her uniform! This girl has talent...but will she get a chance to use it?