The song was first uploaded on August 4, 2012 and not long after on Hitoshizuku-P's YouTube account. It's Hitoshizuku-P's first song in which she illustrates and produces the video herself (an exception for soundless voice and proof of life; in which she made the video but did not illustrate).
"The Wolf that Fell in Love with Little Red Riding Hood" is originally a track for the compilation Dirndl.Frau and is originally sung by the utaites Pokota and Hanatan; however Hitoshizuku-P made a Rin and Len version of the song. Note that this song is still considered as an original song despite the fact that Pokota and Hanatan are the original singers; the song is tagged with "Rin Original Song" and "Len Original Song".
The title of the song; "The wolf that fell in love with little red riding hood" summarizes the plot to the song. Little Red Riding Hood (Rin) questions why she's more or less human and why the Wolf (Len) is who he is. They realize it's forbidden love and nothing can be done but stay a quiet immobile "relationship".