Album: [Demetori] 曼衍珠汝華 ~ Nada Upasana Pundarika
Track: 06. 感情の魔天楼 ~ World's End
Original Game: 東方星蓮船 ~ Undefined Fantastic Object
Original Track: 感情の摩天楼 ~ Cosmic Mind
One of the longest arrangement in the whole album. Do NOT be fooled by the slow and the piano arrangement in the start, it will quickly shift into the metal that you will enjoy. The guitar on this piece is simply marvelous, and the song is primarily focused on the said instrument. It's amazing how just six strings and two hands could create one of the finest arrangement of the album.
EDIT: To anyone wondering, yes, it is 魔天楼 that Demetori chose.