因果律の花 (Ingaritsu no Hana)

==Background==
A young princess (Rin) has a beast inside her castle that awakens every night and kills anyone it comes across. One day she meets a young man (Len) and falls in love with him. She tells him of the beast and he vows to slay it. He takes a sword and goes into the place where the beast sleeps but after he stabs it, he realizes that the beast is actually the princess herself, who is able briefly return to her normal self before dying.
This song is based on the fairy tale The Black Princess.
==Lyrics==
Japanese (日本語歌詞) 	Romaji (ローマ字)
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
、　 	,
　戯れを致しましょう 	tawamure o itashimashou
 	
　、　 	,
　 	
愚かしき花よ、咲け 	orokashiki hana yo, sake
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
 	
　　　 	
魘される 	unasareru
　 	
 	
 	
 	
安らかに眠りましょう 	yasuraka ni nemurimashou
 	
 	
 	
 	
 	
 	
 	
 	
 	
　 	
　 	
残酷な 	zankoku na
 	
 	
 	
 	
黒き闇に消え去った 	kuroki yami ni kiesatta
==Other media appearances==
===Discography===
This song was featured in the following albums: 
* If the World
==External links==
===Unofficial===
Category:Original songs
Category:Japanese songs
Category:Japanese duet songs
Category:Songs featuring Kagamine Len
Category:Songs featuring Kagamine Rin
Category:Songs featured exclusively in albums