Kansuke

"Burn in Hell, Onigumo!"

, also known as was a bandit leader responsible for the near-fatal injury of Onigumo, setting up the tragic events that surrounded the birth of Naraku. 50 years later, Naraku used a dying Kansuke to lure Kikyō to Mount Hakurei.

History
Kansuke, who was originally known as "Rasetsu Kansuke" (羅刹勘助), lead a group of bandit thugs which included a man named Onigumo. After being tricked by Onigumo into attacking the priestess Kikyō in an attempt to acquire the Shikon no Tama, which ended in Kansuke's defeat at the hands of Inuyasha and the loss of his right eye, Kansuke sought to make the man who had tricked him and stolen his men pay. As Onigumo and the rest of the bandits who declared him their new leader celebrated at a local inn, Kansuke planted a bomb which exploded leaving Onigumo severely injured, all of his body was badly burned except for the spider shaped scar that was already on his back. To finish the betrayer off the men threw him off a cliff. This act, unfortunately set the plot of the entire series in motion, making Kansuke the sole perpetrator of not only the creation of Naraku, but the shattering of the Shikon Jewel.

During the story
Fifty years later Kansuke, now an old man, met the revived Kikyō not realizing that she was the same Kikyō he had tried to kill decades earlier. The man is later attacked and killed by demons but before he draws his final breath, Kansuke asks Kikyō to take a lock of his hair to the sacred Mount Hakurei. Naraku had filled his heads with thoughts that he would be properly saved if his remains were taken to Mount Hakurei. But instead it was Naraku's plan to lure Kikyō there so he could test out if he could kill Kikyō and that Onigumo's heart would not stop that.

Personality
As a young man, Rasetsu was a violent, impulsive, and vengeful man who did whatever he pleased. He committed every crime known to man believing that he would die at a young age. He had no tolerance for treachery the perfect example being when Onigumo set him up to be killed by Inuyasha, when trying to take the Shikon Jewel from her. He did not hesitate to try and kill Onigumo by blowing up the inn that he found him in as punishment for almost sending him to his death and stealing his men. As Rasetsu aged, he became more frustrated as he lived a longer life than he expected to. This emulated a fear of dying seeing as how he would more than likely be going to Hell due to his past crimes. As an old man, he wishes for salvation when he hears about Mount Hakurei, a place where villians such as himself can have their souls purified. Before he dies, he cuts off a lock of his hair to Kikyo and asks her to bury it there so that he can be forgiven for the life that he lived.

Weapon
Rasetsu possessed a bow and arrow, and was a fairly skilled archer.

Manga vs. Anime

 * Unlike the anime version of Kansuke, in the manga he was an old and weak bandit without mentioning his name. During his first appearance of manga, he managed to stop a travelling priestess, Kikyō, who was passing by and told that he could feel Kikyō's divine powers. While holding his last breath, he cut off his hair and gave to Kikyō as an, hoping that she would accomplish his request by sending the hair to Mount Hakurei for expiate purpose.
 * Apart from the difference of his history, in the anime Kansuke wears eye-patch on his right eye, but in the manga he wears nothing. Moreover he doesn't wield any Shikon shards.