The two crows at the end... Absolute Cinema
The dialogue Satoko and Konoha have at the end is the thesis of the whole manga. We watched Satoko and Konoha grow from using each other just to survive and do work, to being genuinely in love with each other to the point they will carry each other's burden and be willing to go to hell together. In that togetherness, both of them found happiness and purpose, an escape from a brutal, mundane life. Satoko found genuine connection and comfort that was absent in the village and Konoha learned to love and see life more than work.
The inclusion of the Marin clones ties into this thematically as well. They want to live what little life they have with purpose and assume it would come in the form of being tools for Konoha's goal. Konoha would definitely use them if it were chapter one, but she's clearly conflicted. Even if there are many and their lives are short, they are not expendable. She would only accept it if it means that Satoko would work with Momoji to live a normal life helping others. She does not believe that she can live a normal life, choosing to go without satoko to her death wish. Konoha is still under the impression that it would bring her meaning, but she is likely being used as a tool by the organization. The Marin clones are similar in that they want to be used as tools for her mission, not knowing what Konoha desires deep down.
Satoko rejects the idea to work for Momoji alone because she understands what she and Konoha want. She wants to be with Konoha so much that a robot based on her will betray her creator and blow up the earth for her. She knows Konoha just wants to be loved, and Satoko will do anything to give her that love, even if Konoha does not believe she deserves it.
The world of Ninkoro is pretty cruel, just look at Yoshida, but despite how prevalent death is prevalent in this world, with ninjas slaughtered left and right and money being traded in for lives, Ninkoro is all about celebrating life, purpose, and togetherness.
