That drama is about the love story between an older man involved in underground business and a young and innocent looking man. The pursuit of a place to rest and a family give a similar vibe even if the storyline is really different
Although the plots are very different, they are very short dramas. LGBT+ romances. Quickies (can be considered movie-length). You don't need to think much. Just enjoy.
Both are short BL shows with main character(s) associated with gangsters. While red balloon differs in that the main characters are teens for most of the story, and it’s less intense than long time no see, both have very heartwarming and convincing relationships between the main characters, and interesting side characters.