As the name suggests it, I'm finding for a cover of Karakuri Burst by Hitoshizuku-P and Yama-P. It was sung by a woman with elegant and mature yet powerful vocals (kind of like Wotamin or Hanatan but her voice was much more powerful. She also sung the song as if she was really a psycho who wanted to kill people. She was wild and it was amazing), and a man with a deep, cool vocals that can be rough and powerful at times (I don't know who I could resemble his voice with but it's badass ikemen. He also sung his part perfectly, it was cold and cruel yet determined to make of his view of justice, and I can't get over it).
I remember seeing it at YouTube with my siblings around 2010-2012, and the names were under Kagamine Rin and Len Append which is obviously not the case. One day, it vanished at YouTube even though it always showed up first at the result list and I remember searching for it all over YT that time to find nothing. I believe my older brother still has the audio, I'll try to get it from him if I have the chance.
But for the time being, please help me find that cover with the details I've stated! Even if you're not sure, please show it to me! I'm desperate to find it. It's been stuck in my head for years now, and it's frustrating not to be able to actually hear it! The way the singers sung it with matching emotions to the characters they were playing as if it is them is just perfect! I really, really want to hear them sing it again, and more covers by them! I've also checked all the covers at the Karakuri Burst page here and nobody matched their vocals. So, please help me find it!