Osamu explains to Yūma and Replica that Chika attracts Neighbors and is also able to feel their presence. After moving to Yumide City Station to talk more reservedly, Yūma explains to them why Neighbors invade the city, and Replica offers to measure her Trion, while Osamu and Yūma talk. Shūji Miwa and Yōsuke Yoneya of Miwa Unit see Chika with Replica and assume she's a Neighbor, but Yūma states that he is the real Neighbor and a combat ensues between him and Miwa Unit.
When Osamu saves Chika from the Vander, his victory is noted by Headquarters and especially the Commander-in-Chief. While Replica senses no Rads coming from the Vander's remains, he suggests they move to a different place to discuss Chika's Side Effect, since other Border agents are nearby.
The group moves to an abandoned train station in the Forbidden Zone. Yūma is disappointed there are no trains and is interrupted by Osamu when he is about to tell Chika that he is a Neighbor. Osamu formally introduces the two, and Chika mistakenly assumes that Yūma must be part of Border. As Yūma says that Trion is the only reason the Neighbors are targeting Chika, a small group appears walking toward the train station.
Yūma further explains that Neighbors come to this world to collect people with high levels of Trion and the Trion glands of people with low levels of Trion and take them back to fight battles in their world. Based on this information, Yūma assumes that Chika's Trion ability must be very high and suggests they use Replica to measure the actual level. To reassure Chika, Osamu measures his Trion level first. It appears as a bright cube floating in the air. Yūma states that he would need three times this level to be targeted by Neighbors.
As Chika's Trion level is measured, Yūma asks Osamu if he and Chika are dating. A flustered Osamu quickly denies this, claiming that Chika is merely the little sister of his senpai, Rinji Amatori. Yūma inquires as to why Chika has never gone to Border for help, and Osamu explains that six months ago, Rinji told him that Chika was first targeted by Neighbors before Border existed, so no one believed her when she asked for help. When she finally had a friend who believed her story, her friend disappeared. Chika's Trion level appears and the cube's huge size shocks them all. Replica states he's never seen a Trion gland that big. Replica states that the best course of action would be to ask Border for help, but Chika again refuses. Just then, Shūji Miwa and Yōsuke Yoneya appear. Miwa reports to someone on the phone that they've seen Replica and will eliminate the Neighbor.
Miwa and Yoneya activate their Triggers and advance. They mistake Chika for the Neighbor, since they saw her using Replica. Yūma calmly interjects the he is the Neighbor, and Miwa shoots him without warning. Miwa declares he will kill every Neighbor, since that is his job as a Border agent. Yūma activated a shield just before he was hit; however, and is unharmed. He mentions that he knows Yūichi Jin and says they can ask Jin about him. Miwa calls Jin a traitor and tells Osamu to step aside or he will use force to remove him. Yūma also asks Osamu to stand back and activates Replica. Yoneya asks to fight Yūma one-on-one, but Miwa says it will take the two of them to defeat him. Yūma's pupils turn white and he calls Miwa an interesting liar. At a distance, two more members of Miwa Unit, Shōhei Kodera and Tōru Narasaka, have sniper rifles pointed at them. Kodera is surprised Yūma knew they were there, but Narasaka thinks Yūma is bluffing.
Yoneya is able to cut Yūma's neck, which surprises him. Osamu is shocked, since he has never seen Yūma injured in all the fights so far and worries Yūma is outmatched against A-Rank agents. Osamu calls Jin for help, who is also watching from a distance. Jin tells Osamu to sit back and watch, because although Miwa Unit is highly skilled, Yūma is extraordinary. As they begin to fight, it looks as if Yūma is slightly overwhelmed. As he jumps into the air, Narasaka fires his weapon and Osamu screams Yūma's name.
Characters in order of appearance
- Osamu Mikumo
- Yūma Kuga
- Chika Amatori
- Kyōko Sawamura
- Masafumi Shinoda
- Masamune Kido
- Rinji Amatori (Flashback) (Debut)
- Aoba Harukawa (Flashback)
- Shūji Miwa
- Yōsuke Yoneya
- Shōhei Kodera (Debut)
- Tōru Narasaka
- Yūichi Jin