Based on search data, these are the shows people currently need subtitles for the most:
: One of the largest global databases for multi-language subtitles, including a vast section for Korean TV shows. Korean Series English Subtitles Download
Technically, there are third-party tools (like OpenSubtitle Extractors for Netflix Blu-ray rips), but circumventing DRM protection is a legal gray area. For the average user, using the streaming app’s offline download feature is the safest bet. Based on search data, these are the shows