A vocational school student named Kache works at a concept cafe and is a devoted viewer of an online streamer known as KAngel, or the Super Cute Angel. KAngel, whose real name is Ame-chan, is an internet celebrity who claims the title of Internet Angel and enjoys support from a wide range of generations. Kache soon discovers that one of her classmates is also a member of a streaming group.

The story is set in the chaotic online landscape of Reiwa-era Japan, following the multi-ending adventure from the original 2022 indie game, which depicted a thirty-day period in the life of a young woman with a strong need for approval who aims to become the strongest streamer. The narrative focuses on the intense relationship between Ame-chan, a mentally fragile girl who has dropped out of school, and her boyfriend and producer known as P-chan. To escape her reality, Ame-chan transforms into the colorful and upbeat persona KAngel to interact with her audience, navigating the pressures of parasocial relationships and the dark side of fame.

As a theatrical pre-screening of the upcoming television series, the film is a re-edited version of the early episodes. It explores the push-and-pull between Ame-chan's private despair and her public persona, highlighting her struggles with stress and a dependency on validation from both her viewers and P-chan. The narrative arc focuses on the beginning of her journey to become the number one Internet Angel, establishing the unstable foundation of her streaming career and her complex, co-dependent relationship with her producer.