Lee Sang-jun

BLGLFlix editorial view

He is usually introduced through the tvN music drama. The credit this site exists for is the other one. Heesu in Class 2 is a Korean Boys’ Love series, adapted from a manhwa, ten episodes, and he is billed second in it.

The full filmography illustrates something coverage of this genre keeps getting wrong. He has been working since 2017 and 2021 was a year with four credits in it, including a single episode of Squid Game as one of the masked guards. The BL sits in the middle of a normal Korean television career rather than at the edge of it, and the distinction matters, because English-language coverage tends to sort Korean actors into “BL actors” and “real actors” as though the two were different professions. On the evidence of this record they are the same profession, and he did a fifty-episode daily drama the year before the BL and a tvN music series the year after.

Four Hands, Two Sonatas is also worth a note for its release shape. TMDB records twelve episodes across 29 and 30 August 2026: a two-day drop rather than a weekly run, on tvN, from Studio Dragon. Korean broadcast drama has been experimenting with binge releases and this is one of them, which is not something a reader would guess from an episode count alone.

Finally, the classification. Four Hands, Two Sonatas is filed here as a bromance, not a BL, and it will not be quietly reclassified because the audience for this site would like it to be one. It is a music-school rivalry story about two pianists, TMDB tags it bromance, and if the series itself goes further than that the record here should change on the basis of the series rather than on the basis of hope. Heesu in Class 2 is his BL. The other is not.