Short answers, pulled from the story.
F.A.N.G is a tall and spindly member of M. Bison's villainous organization Shadaloo who speaks with a high-pitched voice. He serves as the story's overall secondary antagonist opposing Karin Kanzuki's faction during A Shadow Falls.
Capcom unveiled F.A.N.G in 2016 as one of sixteen playable characters for Street Fighter V. The name stands for Fantastic Asian Notorious Gang which Capcom revealed through their official Twitter account in February 2020.
Players must maintain button presses for two seconds in various directions to execute moves properly because F.A.N.G is a charge character. His primary tactic involves keeping opponents perpetually poisoned to wear them down before making opportunistic attacks with long reach.
Following Bison's death, F.A.N.G retreats to Shanghai to revive the organization and takes in a teenage prostitute named Phantom. In Street Fighter V Side Story: Toxicity he survives the fall of Shadaloo and focuses efforts on reviving the organization while training Phantom as his protégé.
F.A.N.G consistently ranks as the least used character in Street Fighter V across casual and professional play. He placed 78th in a worldwide Street Fighter character poll held between 2017 and 2018 and subsequent evaluations ranked him very low on tier lists crowd-sourced by the game's player community.