Chojusen looked at the man that chose to kill himself and tears started falling from his eyes. Even though he didn't personally choose to kill the man, he felt like it was all his fault. The man looked back at Chojusen, there was blood leaking from his mouth. He said "Look kid, Its not worth losing your girlfriend for me. If you don't kill me now, not only will I die in vain, you and your girlfriend won't be spared from Danzo's wrath either!"
Hearing the man's final words, Chojusen nodded his head and finished the man off by slicing his throat with the kunai. As he completed this action, he dropped the kunai to the floor and weeped on the floor for killing a person for the first time. Chojusen kept sobbing for minutes and eventually lied motionlessly on the floor.
Danzo left Chojusen to do as he wished after killing a person for the first time. Even he still remembered the first time he killed a man. While he was a cold and heartless monster now, he was also once a greenhorn like Chojusen.
As Chojusen stopped crying, a system prompt sounded off in his mind, but he was too emotional to understand what it said. Chojusen got up from the floor and turned to Danzo. With his eyes still closed Chojusen began crying tears of blood and his eyes involuntarily transformed into his Fiendgod Eyes. However, when Chojusen opened his eyes they were no longer the normal Fiendgod eyes, instead the vector black pupils now formed a red dot in the center. These red dots were ghastly and would leave behind a ghost trail of red neon light whenever Chojusen moved.
Chojusen looked at Danzo with real killing intent and walked over to him slowly. Danzo was frozen in fear and tried to activate the curse mark in Chojusen's time several times to no avail. Losing all hope he activated the last resort function of the curse seal to kill Chojusen, but that didn't work either.
Right now, Chojusen was in what the system would call a "very distressed state" so for now, the limiter would not be working against Chojusen. Danzo chose to strike Chojusen first, hoping to land a sneak attack, but Chojusen was no longer restrained, moreover he had his Fiendgod Eyes activated; to him, Danzo looked like he was barely moving.
Chojusen punched Danzo's body into a mangled corpse, but then noticed that it was just a mass of highly condensed Yin Law constructs. Chojusen turned around to see Danzo stare at him with pure unadulterated fear. Danzo tried to leave, but Chojusen just punched him again. This cycle of Danzo surviving his blows lasted for seven rounds, before Chojusen noticed that the eyeballs on his arm were closing each time he survived what would otherwise instakill him.
Connecting the dots, Chojusen didn't aim for Danzo's body and instead used Wind Elemental coating on his hand to cut off Danzo's arm. Unsurprisingly, after Danzo lost the arm full of Sharingans, he could no longer use Izanagi to survive Chojusen's attacks. For one final time, Chojusen punched Danzo's body, but before he could connect the punch Danzo starting yelling like a mad man, saying "You've forced me to do this! Even If I can't survive this ordeal, I will still take you down with me! Reverse Four Symbols Sealing!"
Symbols began to appear on Danzo's chest and black ink-like liquid started spurting out of the symbols like blood from a wound. A black sphere materialized, surrounding Chojusen and Danzo and Chojusen was pulled towards the center of the sphere. He used Void Cloak to become incorporeal and waited for the black sphere to dissipate.
When the black sphere was gone, nothing was left of Danzo's corpse. With Danzo dead, everyone that had the Cursed Tongue Eradication Seal, including Chojusen, were relieved of its restrain.
Chojusen wanted to be left alone now, so he teleported himself out to his personal dimension. Chojusen spent a good while calming down; it helped that his personal dimension was full of calming environments like mountains, valleys, and lakes. Chokogo had been in his personal dimension all this time and she noticed Chojusen's unstable condition, so she tried to comfort him by staying next to him. When he was fully calmed down, Chojusen said to the system "Why did you purposely play me like that!"
[You had to get over killing people at some point. I figured now would be as good a time as any. Besides, now that you learned the Omniseal Unlock Skill, you probably won't be in a situation like that again.]
"I had to get over killing a person? How could you have possibly known that Danzo would pick for me to kill someone for the first task?"
[Well, if you knew the history of Root and how extreme they are, it wouldn't be hard to guess that he would want you to kill someone to prove your loyalty sooner rather than later.
It seems you still haven't gotten it through your head that this is a dog eat dog world. First it was your encounter with Rasa; if anyone else were in your position, they would not hesitate to kill him after he tried to assassinate you. And now if you weren't forced to kill that prisoner and unlocked the second stage of your Fiendgod Eyes, you probably would have chosen to spare Danzo after learning how to get rid of his curse seal.
The method to make you get over killing people might have been a bit unorthodox, but everything I do is to support your growth. Do you understand?]
"Alright… Now what's this about unlocking the second stage of my Fiendgod Eyes?"
[You probably didn't hear the notification because you were distressed, so I'll repeat it. Host has evolved Fiendgod Eyes to Stage 2
Fiendgod Eyes (Stage 2 | 0/100): Special eyes that grant the user multiple spacetime abilities. These eyes can be used outside of Fiendgod Butterfly Sage Mode. Current Effect: (Stage 1) Allows the user to perceive time three times as fast. (Stage 2) Allows the user to stop spacetime from effecting his body for five minute, but can only be used once a day.]
Chojusen left his personal dimension and teleported back to the Hidden Leaf Village. He walked over to Minato's office and told him about his encounter with Danzo. Minato found it hard to believe Chojusen, as he didn't have any proof to validate his claims. So, Chojusen just told Minato that he would believe him after not hearing word about Danzo in the coming days.
Chojusen went back to Karin's house and let her know that he was ok, before returning to his own house and going to sleep. After getting his Yang Awakening Skill, Chojusen never took a day off training at night to sleep, so his exhaustion could be imagined. After killing a person, Chojusen had changed subtly and everyone he interacted with thereon noticed it.
Chojusen took a couple days to return back to normal, evident in his lackluster training sessions with Karin, Sakura, and Ino. But time heals all wounds, so he got over it eventually.