Crimson Heart

Mysterious blue fireflies have slowly made their way through a crack in the protective dome over the city of Refugia. Although they appear harmless, a single touch can transform a human into a disfigured, mindless monster. Despite providing their citizens with comfortable lives and the latest technology, Refugia's controlling government conceals this danger from the public.

Four young girls—Sena, Dabi, Yojae, and Joan—join a unit entrusted with testing a new security system. But when they come too close to the confidential secrets of Refugia and have an unfortunate encounter with the blue fireflies, they are magically teleported outside the dome. Only vaguely aware that this is their first breath of true freedom, the girls decide to investigate the world beyond.

Guided by a hidden clue, the girls search for the mystic Blue Firefly Island and the secret behind a magical necklace that comes into their possession. Armed with optimism, the girls embark on their first-ever adventure, where the outside offers revelations about Refugia and its corrupt rule—as well as dark truths that will forever change the world as they know it.

[Written by MAL Rewrite]

Edit
Background

Crimson Heart resulted from a collaboration between Webtoon Entertainment and Hybe Corporation. It is a part of Le Sserafim's Crimson Heart universe, with five of the main characters representing members of the K-pop group.

A booklet of the webtoon's prologue was featured in the group's mini album "Antifragile," released on October 17, 2022. Le Sserafim's song "Blue Flame" serves as the webtoon's official theme song. The complete story of Crimson Heart is told not only through the webtoon but also via the group's music and promotional videos that are marked as official Crimson Heart content.

The series has been published digitally in English, French, Spanish, German, Indonesian, Chinese, and Thai by Webtoon Entertainment.

More characters
Characters

Dabi

Main

Yurina

Main

Yojae

Main

Looisha

Main

Joan

Main

Sena

Main

Reviews

Dec 2, 2023

SpongyMallard

Mixed Feelings

Preliminary (53/53 eps)

Spoiler

A Very Good Story Until the End.

Unfortunately, it seems the popularity dropped enough to rush the ending. Until chapter 40ish it was going great with the pacing, world building, character development and such. Sadly, not soon after it was becoming clear that the ending was going to be rushed out the doors.

The last two girls who get added to the party have it the worst as we learn basically nothing about them, their powers or anything.
Joan’s arc is kinda weird as we learn a lot about her, but aspects added later get no development due to the rushed ending. The ending itself ...