Chika Amatori/Plot

Background
Chika, possessing an absurd amount of Trion, was the frequent target of Trion Warriors. One day, her friend Aoba Harukawa was taken by Trion Warriors; in the anime, she was at the scene of the kidnapping. This served as a traumatic experience for her, which was only worsened several years later, when her brother Rinji disappeared. She blamed herself for the two losses, which led her to leading a more secluded lifestyle.

Introduction Arc
Chika is first seen in the end of Chapter 11, going to a bridge. In the next chapter, waiting for Osamu she's under the bridge. She checks the time on her cell phone, saying she seems to have arrived too soon. She then hears a noise and turns around to see Yūma, who fell to the ground while riding a bicycle. She asks him if he's alright, and he says he is.

Yūma says he thought there was a trick to holding the bicycle, and is surprised to know there's not. He then asks her if the Japanese received some kind of special training to ride bicycles, which causes Chika to ask herself if he's a foreigner, and he starts riding his bicycle again. While he's riding his bicycle, she answers a call from Osamu, and Yūma falls again. She then starts pushing him in the bicycle, which helps him learn how to, but causes him to fall inside the water.

After Yūma gets out of the water, he cleans himself, and they then introduce themselves to each other. Chika then notices something, and the Danger Alarm starts ringing. Yūma says it seems to be near, and that it must be in the danger zone. Chika then runs out, saying she has to go.

She sneaks into the danger zone, where she sees a Trion Soldier. Chika tries to clear her mind but her cell phone starts ringing, causing the Neighbor to see her. But before it can attack her, she's saved by Yūma, and then Osamu arrives and destroys it. Osamu, who called them both so that they could meet each other, then says he needs information from Yūma and Replica, saying Chika attracts Trion Soldiers.

Replica measures Chika's trion level and finds that it is enormous. This triggers the suspicion of the Miwa Unit, and they reveal themselves, believing Chika to be a Neighbor. Yūma clarifies that he is the Neighbor, and then they engage in a battle with him.

Border Enlistment Arc

 * Border Member Official Enlistment Day

B-Rank rank battles Arc

 * Tamakoma Second vs. Yoshizato Unit vs. Mamiya Unit: Win
 * Tamakoma Second vs. Suwa Unit vs. Arafune Unit: Win
 * Tamakoma Second vs. Suzunari First vs. Nasu Unit: Win
 * Tamakoma Second vs. Ninomiya Unit vs. Kageura Unit vs. Azuma Unit: Loss (Ninomiya Unit's victory)
 * Tamakoma Second vs. Katori Unit vs. Kakizaki Unit: Win
 * Tamakoma Second vs. Ōji Unit vs. Ikoma Unit: Win
 * Tamakoma Second vs. Kageura Unit vs. Azuma Unit vs. Suzunari First: Win