鬼姫と花嵐 (Onihime to Hanaarashi)

Background
The song was first uploaded on October 12, 2011; it is overall Mermaid-P's most notable work (the others being "Mermaid" sung by Kagamine Rin and "HEART" by Nekomura Iroha). It's also Mermaid-P's second work to be voted on JOYSOUND (the first being "HEART").

It's featured in the folk album compilation 花楽里漫葉集 as one of the tracks in the compilation (available in the CD track, and also the video as a DVD).

It tells a story of a demon (Rin) who was once a human. She slays humans, and, a demon slayer (Len) was out hunting for her. Unfortunately the two fell in love, aware of the fact that they could never be together, Rin killed him. In the end, however, it's shown that Len wasn't dead yet; he bit Rin's finger, drank her blood, and became a demon just like her.

Note: The gibberish parts of the lyrics in the song has no definite meaning and is just plain gibberish.