闫东炜 made "萤火虫の怨" available on June 20, 2019. The duration of 萤火虫の怨 is about two minutes long, specifically at 2:40. This song does not appear to have any foul language. 萤火虫の怨's duration is considered a little bit shorter than the average duration of a typical track. There is only one song in 风屿, so we believe that "萤火虫の怨" is a single. In terms of popularity, 萤火虫の怨 is currently below average in popularity. The overall tone is very danceable, especially with its high energy, which produces more of a euphoric, cheerful, or happy vibe.
The tempo marking of 萤火虫の怨 by 闫东炜 is Andante (at a walking pace), since this song has a tempo of 100 テンポ. With that information, we can conclude that the song has a slow tempo. The time signature for this track is 4/4.
A Minor is the music key of this track. Because this track belongs in the A Minor key, the camelot key is 8A. So, the perfect camelot match for 8A would be either 8A or 7B. While, a low energy boost can consist of either 8B or 9A. For moderate energy boost, you would use 5A and a high energy boost can either be 10A or 3A. However, if you are looking for a low energy drop, finding a song with a camelot key of 7A would be a great choice. Where 11A would give you a moderate drop, and 6A or 1A would be a high energy drop. Lastly, 11B allows you to change the mood.