The battle between Yūma and Shun begins, with Shun getting the upper hand in the first two rounds, surprising Osamu and Yōtarō, the latter who gets angered at this. Yoneya explains that it's about the difference in experience, and Yōtarō says that shouldn't matter, but Yōsuke says that's not what he means. After losing the first two rounds, Yūma then gets the upper hand, defeating Shun in all subsequent rounds. In the last round, Shun decides to battle Yūma head on, again losing. After the battle, Shun apologizes Osamu in front of so many people, as it was proposital, but Osamu takes the chance to explain that he actually lost to Kazama 24 rounds and only got a draw in one round. Jin then comes to call Osamu and Yūma to a meeting, with Shun greeting him. Jin, Osamu and Yūma then go to the meeting room, accompanied by Yōtarō mounted in Raijinmaru. There, Border's leaders explain about the upcoming invasion and enlist Yūma's help in identifying the attacking country and preparing for the invasion. Yūma introduces them to Replica, who offers to give them the information they want if they promise to protect Yūma. Kido accepts his offer, and Replica begins his explaination.
Osamu calls out to Yūma, who walked into the room without acknowledging him. Yoneya then walks up beside him and sighs that Yūma promised him a fight first. Yōtarō adds that Yoneya is Shiori's cousin and one of his "Yo" friends.
Inside the staging area, Midorikawa instructs Yūma how to accept a fight with an official agent. Since he cannot receive points from beating Yūma, Midorikawa suggests he take points from Osamu instead. Yūma agrees, saying only if Midorikawa wins. Thinking of his time with Kirie, Yūma suggests going for ten rounds. In the lobby, Osamu is surprised to learn that Midorikawa belongs to an A-Rank no. 4 Unit. Quickly, Yūma loses the first two rounds. Spectators, including Osamu, are in awe of the ostensible difference between A-Rank and rookie agents. Yoneya says there is a huge difference in experience, but referring to Yūma's experience, not Midorikawa's. Yūma wins one round, and Yoneya says that since Yūma beat four members of Miwa Unit, there's no way he'd lose to one person. He adds that it seems Yūma really wants to beat up Midorikawa. Yūma then proceeds to win two straight rounds, confusing Midorikawa.
Yoneya says that since Midorikawa joined about a year ago, he constantly wants to himself. Yūma, on the other hand, has the movements of someone who will absolutely defeat his enemy. Yūma continues to win and confronts Midorikawa about attempting to ruin Osamu's reputation, saying he will defeat Midorikawa in Osamu's place so he will never try anything like that again. Midorikawa actually smiles and remarks to himself that Yūma is strong.
In the meeting room, Kazama notices that Yūma is soundly beating Midorikawa, and Jin notices that Yūma only let Midorikawa win in the beginning. Kinuta tells Kido that he isn't sure if they can trust Yūma, but they should use him if he has information.
In the tenth round, Yūma asks Midorikawa why he doesn't use other Triggers. and he explains this way their differences are understood. Yūma quickly defeats Midorikawa and walks out to join Osamu, Yoneya, and Yōtarō. Jin walks up and asks Yūma and Osamu follow him to see Kido. When some of the trainees refer to him as S-Rank, Jin happily informs them that he is now A-Rank. Midorikawa runs up to Jin and cheers his name and begs for a match. Yoneya informs Yūma and Osamu that Jin saved Midorikawa from a Neighbor and that is why he joined Border. Midorikawa then calls Osamu "senpai" and apologizes for trying to purposefully humiliate him in front of others. Osamu is relieved to admit that he lost 24 times to Kazama and that the rumor about his tie was blown out of proportion. Yūma and Midorikawa reconcile and form a friendly rivalry. Midorikawa asks Jin to let him join Tamakoma if he defeats Yūma. Osamu, Yūma, and Yōtarō astride Raijinmaru leave with Jin, and Yoneya pouts that he wasn't able to fight Yūma. The spectators whisper about Yūma's amazing victory, but also about the mysterious Osamu, who Yūma calls "captain" and seems to be close to Jin and Kido.
Jin asks Yūma and Osamu about their impressions fighting Midorikawa. Yūma calls him strong, but Osamu admits he couldn't read him at all. Yūma then explains he usually fights people as if they are animals. His father once told him that since humans are illogical, it is sometimes better to examine people's behaviors than logic. Disheartened by the realization of the difference in strength and ability between himself and Yūma, and understanding how hard he will have to train in order to catch up to other people working hard, Osamu stands in the elevator muttering to himself after the others have exited. Yōtarō calls him back to reality.
They enter a room with a large virtual display and are greeted roughly by the head staff of Border. Shinoda explains that they anticipate a large attack in the near future. After the bombing incident where many people were injured, they are looking for ways to reduce injuries and ask for Yūma's opinion as a Neighbor. Kinuta explains further that they haven't been able to gather enough information and as a Border agent they expect Yūma to give them his opinion or which country might attack and what kind of attacks might be used. Yūma says it would be better to ask his partner, and Replica emerges from his sleeve, surprising everyone. Replica introduces himself as a special Trion Warrior created by Kuga Yugo and affirms that he has information from traveling around the Neighborhood. Before Replica will give them the information; however, he demands that Yūma's safety be guaranteed by Kido. Osamu realizes that Yūma is testing Kido with his Side Effect. Kido quickly agrees, saying that as long as Yūma follows Border regulations, he will be protected. Yūma doesn't react, leading Osamu to believe Kido is telling the truth, and Replica proceeds to tell them about Neighbors.