Suikotsu

was a member of the Shichinintai. Like the others, he loved carnage and killing; however, unlike them, he had a split personality. This personality was that of a kind-hearted doctor, who may have been the original personality until a traumatic event caused the birth of his other, more bloodthirsty, personality.

History
Suikotsu started out as a traveling doctor, but seeing so much death and bloodshed due to war began to affect him psychologically. He finally snapped when he killed a soldier out of self-defense. Knowing that he killed someone caused him to develop a new personality that enjoyed killing others. His killing streak would cause him to cross paths with Bankotsu and join his band of mercenaries that would come to be known as the Shichinintai.

Suikotsu and the rest of the Shichinintai took a job for a lord. They were soon betrayed by the lord due to the Shichinintai being considered too dangerous to exist. They fled into the mountains, but they were soon captured and executed. Suikotsu and the other Shichinintai members would then be revived fifteen years later when Naraku would give Bankotsu seven Sacred Jewel shards.

During the story
Suikotsu had no memory of his time as a mercenary and was looking after orphans in a small house near Mount Hakurei. The people of the village that he came across were initially scared of him since he had the same name as one of the Shichinintai mercenaries that were rumored to have been revived, but quickly accepted him when they saw how kind he was.

Suikotsu was met by the priestess Kikyō while tending to an elderly woman. She could sense a Shikon Jewel shard in his neck, but was puzzled by it because it was not corrupt. Two villagers later approached him when one of them injured their leg. Suikotsu began to feel unwell after seeing so much blood from the villager's wound. He had Kikyō finish healing the wound when he was unable to proceed due to his fear of blood. He later explained his fear of blood to Kikyō and how he first arrived in the area as a traveling doctor. He suddenly began to hallucinate seeing blood on his hands and frantically tried to wash it away. Kikyō stayed with Suikotsu for several days in an effort to understand why the jewel shard that he possessed was not tainted with evil.

Suikotsu began to have nightmares about his traumatic past and how his evil persona began to take over. He later left with the orphans Yūta and Chiyo to pick medicinal herbs. It was then that he was approached by Inuyasha and his friends when Kagome was able to sense his jewel shard. Unaware that Suikotsu had no memory of his time as a mercenary, Inuyasha immediately attacked him after detecting the smell of graveyard soil and corpse from him. He managed to push Suikotsu down the hillside. The two orphan children tried to defend Suikotsu from Inuyasha. Miroku believed that Suikotsu was not a member of the Shichinintai based on his behavior, but Inuyasha believed that it was all an act to lower their guard. Suddenly, they saw that the village was under attack. Suikotsu rushed over to help out. It was revealed that the attackers were Renkotsu, Jakotsu, and Ginkotsu in his new tank body. They came to pick up Suikotsu, but he did not remember them. Inuyasha's group arrived soon after and were surprised to see that Kikyō was there as well. Renkotsu ordered Jakotsu to deal with Suikotsu. Still unaware as to why they were after him, Suikotsu begged that they spare the village and only kill him. Jakotsu was annoyed with Suikotsu's good persona and began to attack him with his sword. He was saved when Kikyō shot her sacred arrow at Jakotsu. Renkotsu had Ginkotsu fire on Kikyō and Suikotsu with his cannons. The shot caused both of them to be momentarily knocked out. Kikyō began to lose some of the dead souls in her body. Suikotsu awoke and was about to tend to her when Yūta and Chiyo ran after him out of concern. Suikotsu warned them to stay away since it was too dangerous. Jakotsu was prepared to kill the two children with his sword, but Suikotsu blocked the attack and got his shoulder severely injured as a result. The injury caused him to have a psychotic break. His evil personality awoke and started to strangle Yūta, but was stoped by Inuyasha's Sankon Tessō.

Suikotsu expressed delight that he was no long bound by his persona of "that ridiculous do-gooder physician." It was then that Kagome realized the Suikotsu possessed a split personality. The other members of the Shichinintai were glad that the evil Suikotsu had awakened and Renkotsu tossed a pair of tiger claws at him. He was now eager to fight Inuyasha. Suikotsu was able to predict Inuyasha's moves and forced him on the defensive. He managed to land a few shots with his tiger claws and caused Inuyasha to trip. He was about to dig his claws into Inuyasha's throat, but was stopped after Yūta and Chiyo begged him to turn back the kind doctor that they knew. Suikotsu began to lose his grip on his evil side, but was able to halt Inuyasha's efforts into rescuing Kikyō when the other members of the Shichinintai approached her unconscious body. It was later revealed to be a distraction so Jakotsu could kill Yūta and Chiyo to ensure that Suikotsu would not revert to his good persona. Suikotsu partially reverted and pleaded for the children's safety. Renkotsu began to suspect that it was the purifying barrier of Mount Hakurei that was preventing Suikotsu from fully turning into his evil side. Renkotsu ordered the rest of the Shichinintai to retreat. Jakotsu grabbed Suikotsu since he was still torn between his two personalities. Inuyasha tried to stop them with the Kaze no Kizu, but was stopped by Ginkotsu's cannon fire before he could unleash his attack.

Suikotsu and the others joined up with Bankotsu. They attacked the castle of the lord that betrayed them. After they destroyed the castle, they were approached by Kōga. Inuyasha's group arrived shortly thereafter. Suikotsu fought against Miroku; professing his hatred towards monks and doctors. The Shichinintai made a retreat after being ordered to by Naraku's saimyōshō. They met up with Kanna and Kohaku at the base of Mount Hakurei, and were given new orders to kill Sesshōmaru with the rest of Naraku's enemies. Bankotsu ordered Suikotsu and Jakotsu to kill Sesshōmaru.

The two were planning to ambush Sesshōmaru while moving away from Mount Hakurei's barrier in order to prevent Suikotsu's good personality from appearing. Jakotsu attacked Sesshōmaru, while Suikotsu confronted Jaken and Rin along a wooden bridge. Jaken was able to hold him off with his staff and manages to use its flame attack against him. Suikotsu appeared to have been incinerated, but had actually managed to dodge it by hiding underneath the bridge. The bridge broke as Suikotsu attempted to catch Rin, and all three of them fell down the ravine.

Rin awoke to find herself being carried off by Suikotsu who had reverted to his kind self. Rin was immediately scared after seeing him, but soon began to trust him after seeing that he was different from the person who previously attacked her. Suikotsu decided to take Rin to his house until she could meet up with her companions. Kikyō could sense Suikotsu's jewel shard and followed it after sensing a different presence from it.

The children that he previously tended to were surprised to see him return. He asked them to show Rin around while she would stay with them. Some of the villagers soon arrived and asked Suikotsu to leave since the Shichinintai attacked their village because of him. Suikotsu killed an elderly villager with his tiger claws and sadistically expressed his disappointment that they were acting ungrateful to him after all the times he treated them as a doctor. He killed off the remaining villagers as they attempted to flee. Jakotsu arrived and captured Rin as she was attempting to escape. He asked Suikotsu what happened to him since he was capable of murder while wearing the face of his kind self. Suikotsu was unsure, but claimed that he was his true self now and that he came to the base of Mount Hakurei in order to confirm that his good persona would no longer resurface. He then proceeds to kill the orphans he once took care of. As he was about to strike them, however, he was unable to bring himself to do so. When Jakotsu asked if he would kill them or not, Suikotsu angrily told him to shut up. As he continued to struggle, he began to picture Kikyō's face in his mind that added on to his frustration.

A saimyōshō arrived to warn them that Sesshōmaru would be approaching them soon. The two of them took Rin inside the barrier of Mount Hakurei in order to lure Sesshōmaru and confront him while he was weakened. To their surprise, Sesshōmaru had managed to cut them off along the mountain. Suikotsu held Rin hostage while Jakotsu battled Sesshōmaru. Rin was freed for a moment after Sesshōmaru surprisingly threw his sword at Suikotsu's chest, but he managed to restrain her since he could not be killed by conventional means. He expressed his desire to kill Rin since he knew that her other side would not interfere at the moment, but as he was about to do so, he was struck down by Kikyō's arrow that landed in his throat. Her sudden arrival caused Jakotsu to flee due to his fear of her. As Kikyō approached Suikotsu, she saw that he reverted to his good self due to her arrow. Suikotsu asked her to remove his jewel shard so that he could die peacefully. He had regained his memories of all the evil things that he did, and he wishes to die so that his evil side could no longer kill. As Kilyō was about to honor Suikotsu's last request, Jakotsu violently removed the shard instead. With his final breath, Suikotsu stated that it was finally over and turned into bones. His Shikon Jewel shard was given to Bankotsu.

Personality
Suikotsu suffers from symptoms of dissociative identity disorder. He has two, definite split personalities. One a gentle, philanthropist doctor who looks after orphans, the other a psychopathic and sadistic thrill killer that earns him his place in the Shichinintai. While the doctor is in control, he is has a severe case of that causes him to hallucinate blood on his hands, and can trigger his evil personality. When the mercenary takes hold, he seems to possess a dry sense of humor and an insatiable desire for blood.

Whether out of denial or amnesia from psychological trauma due to the actions of the mercenary, the doctor was unable to remember anything from when the mercenary was in control. The mercenary, however, to his disgust was able to recall everything the doctor did. It was only when Kikyō purified the jewel shard that Dr. Suikotsu was able to recall everything. It was also then that he demonstrated true selflessness, asking her to kill him permanently so he could die in peace and prevent the Shichinintai mercenary from ever killing again.

Physical description
Suikotsu appears as a tall young man with brown hair and pale skin. While Dr. Suikotsu is in control, he has his hair tied back in traditional Japanese knot.

Suikotsu's true appearance is very different from his good half, his facial expressions are described as being quite similar to that of a yōkai. He has six green marks across his face. His hair also appears spiky.

Outfit
Suikotsu wears a matching blue kosode and hakama with a light stripe along his upper body. While he maintains the persona of "Dr. Suikotsu", he also wears a brown traditional haori of a common villager and wears waraji sandals.

In his evil persona, he wears armor that consist of a dark blue breastplate, with three kusazuris that run down his legs, and a green sash around his waist. He also has large black shoulder pads, blue arm guards over his kosode, and a pair of matching kyahan and tabi on his legs.

Powers & Abilities

 * Immense Strength: While his evil self is out, he has athletic attributes that rival those of Bankotsu. Suikotsu is strong enough to be able to fight on equal terms with Inuyasha while he is not using the Tessaiga.
 * Expert Hand-to-Hand Combatant: Suikotsu claims to be an expert of close-range combat.
 * Expert Healer: When he is good, Suikotsu is a skilled healer who can make several remedies with various herbs for various injuries.

Weapons

 * Tiger Claws: Suikotsu wields a pair of tiger claws over his hands as his primary weapon.

Manga vs. Anime

 * The circumstances surrounding Suikotsu's multiple personalities are not revealed in the manga.
 * In the manga, Kikyō discovers Suikotsu's fear of blood after spending time with him after a few days. In the anime, she discovers it soon after first meeting him.
 * The scene in Episode 107 of him imaging the sight of blood on his hands while trying to wash it off is not in the manga.
 * In the manga, Suikotsu does not manage to pin Inuyasha to the ground during his fight against him.

Trivia

 * Suikotsu's name comes from two kanji (睡, "Sui"; 骨, "Kotsu"), and is translated as "sleeping skill," possibly referring to his "sleeping" personality.
 * An elderly villager compares Suikotsu's face to that of a "Rasetsu". It is the Japanese name of a being in called a "". They serve both good and evil and are able to shapeshift.
 * Suikotsu's Theme-Music from the InuYasha Official Soundtrack, Vol. 3 is entitled.
 * Suikotsu's characteristic resembles that in , as the good half is a doctor while the evil half is a mad killer.
 * The marks on Suikotsu's face mean "Fury". In addition, they disappear when his good personality is in control.
 * His eyebrows also disappear when his evil personality surfaces.
 * The evil Suikotsu's "claws" and hairstyle look similar to Wolverine's from . He has even copies some of his more well-known poses, such as crossing his arms over his chest or spreading his arms apart.
 * The change in his hairstyle when is becomes evil is similar to the Super Saiyan transformation in the anime series .
 * The blades of his tiger claws constantly change their size, from being the length of the glove/handle, to being three times as long. The angle of the blades are also inconsistent.

Media appearances
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Manga

 * Chapter 245
 * Chapter 246
 * Chapter 247
 * Chapter 248
 * Chapter 249
 * Chapter 250
 * Chapter 251
 * Chapter 252
 * Chapter 253
 * Chapter 254
 * Chapter 258
 * Chapter 259
 * Chapter 260
 * Chapter 261
 * Chapter 262
 * Chapter 263
 * Chapter 265
 * Chapter 276

Anime
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 * Episode 103
 * Episode 107
 * Episode 108
 * Episode 109
 * Episode 110
 * Episode 111
 * Episode 114
 * Episode 115
 * Episode 116
 * Episode 120
 * Episode 121
 * Episode 122
 * Episode 123