The long-haired character must be the main love interest. Any hair color is okay. This is limited to pseudo-European settings since long-haired MLs are fairly common in Korea/China/Japan-inspired pseudo-historical series. As such, murim is also excluded.
The character should have long hair for the majority (>50%) of the series, so having it cut for a short time is okay. However, if they cut it at the beginning and it remains short, then they won't be included.
Of course, I will not be including any series where the love interest is a spoiler. The male lead should be obvious based on promotional artwork/covers/synopsis. Also, if there are multiple love interests, but all of them have long hair, then that also gets a pass.
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