Crimson Heart

Here's an improved synopsis of "Crimson Heart," incorporating your requirements: "Within the protective dome of Refugia, life is comfortable, technologically advanced, and meticulously controlled. But a sinister threat emerges: ethereal blue fireflies, seeping in through a crack in the dome. Though beautiful, a single touch can transform a human into a grotesque, mindless monster – a danger the city's ruling government desperately conceals. Four young women, Sena, Dabi, Yojae, and Joan, are recruited to test a new security system. However, their proximity to Refugia's hidden truths leads to a fateful encounter with the blue fireflies, resulting in their magical teleportation beyond the dome's confines. For the first time, they breathe true freedom, sparking a desire to explore the unknown world outside. Guided by a cryptic clue and armed with a mysterious red necklace, the girls embark on a quest to find the mythical Blue Firefly Island. Little do they know, their adventure will reveal the shocking secrets of Refugia's corrupt regime and expose dark truths that will shatter their understanding of the world. What awaits them beyond the dome, and can they break the curse of Blue Firefly Island? Read Crimson Heart on capitulos.cloud completely free and without intrusive ads." Read the MANHWA (Coração Carmesim, Corazón Carmesí, Scarlet Heart, 진홍빛 심장 (Jinhongbit Simjang), 深紅の心臓 (Shinku no Shinzou), 绯红之心 (Fēihóng zhī Xīn)) online at Capitulos.Cloud completely free and without ads, with the latest chapters updated.