One of my favourite types of music to listen to are anime/game character songs. I don't see much discussion of them, which is sad because they are awesome!
If you are unaware, character songs are released in Japan to promote anime, manga and games. They're usually released as singles or as part of an album. Sometimes they are used as opening songs for anime or games, like with Diabolik Lovers for example. They are sung by the seiyuu (voice actors) of the various characters. Usually the songs explore the character's motivations or something to do with the plot. Sometimes the songs are just covers, but most of the time they are completely original compositions! A lot of the character songs I have heard seem to follow a similar rock sound, but there are many exceptions to this. The singing is mostly of good quality, because Japanese voice actors are usually trained in this.
Character songs are usually not released outside of Japan. Usually you can find them on YouTube. The CDs for the more recent anime/games can be imported, but for older franchises it can be hard to find the discs for sale. Sometimes you can find them on iTunes or Spotify in other countries, but there aren't too many there.
In the West, character songs are virtually unheard of. The only slightly similar examples I have found are the Equestria Girls character music videos that came out a few years ago. Also, some American TV programmes air those super cringeworthy musical episodes every once in a while, but I don't think those count.
I just love listening to character songs so much! Even if it's from an anime I've never watched, sometimes I'll listen to them because I like the seiyuu. I wish more people knew about these songs, cause they can be quite fun, even if they are basically just advertisements for a show/game. If you want to listen to some, just search your favourite anime on YouTube with "character songs". There is a very high chance that you'll find something to listen to. Some franchises don't have any character songs, but a majority do.