Thread:ComicReadingGamer/@comment-5688420-20180910064919/@comment-5688420-20180914072724

Those songs are called "image songs", which are songs created under the perspecive of a certain character. Image songs are commonplace in popular anime or Japanese video games (and some Western ones as well; "Immortal" by Adema is essentially an image song for Mortal Kombat's Scorpion)