‘Butterfly Doors’ went up on AtHeart’s own YouTube channel in March 2026. The description is unusually bare — a release name, one distribution link and three hashtags — which makes the small formatting choices in it easier to notice.

What the brackets around a name mean

Korean music listings use punctuation as a filing system. Square brackets around a name mark the release — the album, EP or single record — while single quotation marks mark one track on it. Korean portals, distributors and agency notices all follow the convention, so a listing can be read at a glance without any explanatory wording. This upload uses both forms: the video title carries ‘Butterfly Doors’ in quote marks, the description carries [Butterfly Doors] in brackets. A record and a song sharing a name is ordinary in Korea, and the brackets are the only thing telling the two apart.

About this release

The official description names the release as [Butterfly Doors] and gives a single distribution link, published on the group’s own channel on 11 March 2026. It lists no producer, no featured artist and no format label, so whether the record is a single or part of something longer is not stated there. The copyright line reads AtHeart.

Watching from outside Korea

앳하트 is AtHeart written in Hangul. Watch the release in the player on this page and continue exploring OSEYO KOREA’s K-POP section; the article includes only the credits established for this listing.

→ Every AtHeart 앳하트 video on Oseyo Korea

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