LAST ONE I PROMISE, how does Kiryu view Akiyama? What does he think of their history, if he thinks of it at all? Does he regret, or value, having known him?
Akiyama being a recent addition in terms of allies. The way they met certainly wasn't ideal. For he had assumed he was one of the many assailants going after Yasuko. But once he got the full picture. He got a better impression of the man. Most notably when he seemed resilient to simply make back his millions of yen that was swiped under him. Statements like that told Kiryu plenty of the sort resolve that Akiyama had. He would come to regard him more and more as a dependable person. For had been more than grateful of what he had done for Haruka in what capacity he had during her idol days. As well as smeone he would have in a foxhole when it came to aiding him with the triads in Y6 and the whole Iwami Conspiracy. He may have been recent in his life relative to all that has happened. But people like Akiyama showed that there were plenty of people who would do good in keeping Kamurocho safe. One that he would trust without question to keep Kamurocho in a good state. No doubt he skirts the line between the legal and the illegal with his business, but he respects what Akiyama has chosen to do with it. To simply allow people a 2nd chance. Where money problems simply problems that could be easily resolved. One thing that was often a point of disagreement was Akiyama's insistence that he never had any blood on his hand. He didn't feel comfortable with the man trying to deify him as a local legend. Relative to what people already do plenty of times. He understands that Akiyama doesn't want him killing out of emotion. But to say that he is a saint? That is something people have appropriated. He is acutely aware of the blood on his hands. He has killed to defend himself. He is the grey between the black and white. Though he always tries to avoid killing cold blood and resolving issues through talking things out. Even he is not so blind that it can always be this way. It's something that he would be rather blunt to Akiyama. Which only pained him when he had to make high price of sacrifice by 'erasing his name' and to work under the Daidoji for the sake of everyone's safety. No doubt Akiyama would have been very enraged by such a reckless decision, But Kiryu saw no other way that wouldn't cause trouble for those who associated with him. When he found out from Date-san about how Akiyama refused to believe that he died, it really painted a picture of how callous he had been with his companionship due to such brash decisions that would be easy enough fix. He underestimates the powerful weight that he had shaped in Akiyama as well as others in his life.
To wrap this up. Kiryu doesn't regret having met Akiyama. For his help has been nothing short of invaluable during increasingly stressful times. Given the ending of Infinite Wealth. Kiryu is recovering slowly. He has ample time to make his amends, be open with Akiyama and maybe just patch things up. It's been a wild ride for the both of them.
