The song is Regretting what I said by Christine Lavin.
The video uses various anime sources, but the person singing is from Death Note. I like when she took the dog Ien from Cowboy Bebop and composited it on to another clip. She also composited the death note book in the snow scene when the book falls onto the snow.
I always thought that Misa got the shaft in the Death Note anime---she gets used and abused by Light through the whole thing and then basically shoved off to the side for the second half of the series. The creator of the AMV wanted to give her a voice---give her some "teeth" to bite back at Light. She had been a fan of Christine Lavin's for song for years and thought it fit Misa perfectly. I hope you enjoy it.
Death Note and Misa
Death Note and Misa
Raito Yagami is an intelligent young man who resents what appears to be a relentless increase of crime and corruption in the world around him. His life undergoes a drastic change when he discovers a mysterious notebook, known as the "Death Note", lying on the ground. The Death Note's instructions claim that if a human's name is written within it, that person shall die. Light is initially skeptical of the notebook's authenticity, but after experimenting with it, he realizes that the Death Note is real. After meeting with the previous owner of the Death Note, a shinigami named Ryuk, Light seeks to become "the God of the New World" by passing his keen judgment on those he deems to be evil or who get in his way.
Soon, the number of inexplicable deaths of reported criminals catches the attention of theInternational Police Organization and a mysterious detective known only as "L". L quickly learns that the serial killer, dubbed by the public as "Kira" (キラ, derived from the typical Japanese pronunciation of the English word "killer"), is located in Japan. He also concludes that Kira can kill people without laying a finger on them. Light realizes that L will be his greatest nemesis, and a game of psychological cat and mouse between the two begins.
Misa Amane, another Death Note owner, finds Light. Obsessed by Kira after the death of her parents' murderer, she devotes herself to helping Light, but is captured by L. Light makes a plan involving renouncing ownership of both Death Notes, and all of his memories of them, and turns himself in to L for surveillance. Together, Light and L investigate eight people from the company "Yotsuba" who are using Misa's Death Note for their own profit. While arresting them, Light recovers all his memories when he touches the Death Note. He remembers and continues his plan of compelling the former owner of Misa's Death Note, the shinigami Rem, into killing L and his aide Watari.