Satoshi Hiwatari is a genius child who goes to the same school as Daisuke, and also heads up the investigation to capture Dark. Satoshi suspects that Daisuke is Dark, and when Satoshi discovers Daisuke looking up his Alumnus Profile at school, he decides to test his theory. He sets up a trap that locks him and Daisuke in a chilled storage room, and he sets the locks so that even Daisuke can't break the code! Although Satoshi tries to force Dark to appear, Daisuke resists, and eventually Satoshi loses his composure and Krad, Dark’s enemy and “other self”, appears. Daisuke calls Dark and a battle ensues, with neither side winning. After the fight, Satoshi decides to leave school for a while to keep his distance from Daisuke.
On the second floor of a large, messy room, Satoshi Hiwatari sits on his bed, hunched over and exhausted as morning arrives. He looks at his hand, stating aloud that he barely kept his own form. Thoughts of a golden-haired man and a battle are interrupted by an incoming call from his father on his cellphone, which Satoshi merely stares at without answering.
Daisuke Niwa is delighted and surprised when Risa Harada gives him a lunch box as they sit on a bench outside of school and decides he’s the one and only boy she wants to make lunches for every day. He’s brought to tears when she feeds him a delicious bite and hugs her in gratitude, reassuring the girl that he will never let go of her. The hug is returned by Satoshi, who says he will never let go either.The shock jolts Daisuke out of his dream and startles With, who slept nearby. When Daisuke wonders why he dreamt of his classmate, Dark teases him about being in love with Hiwatari and thus losing Risa to Dark. Daisuke vehemently denies this and falls back onto his bed, saying that, even so, the boy has an air of mystery about him.
In the bathroom of their home, Risa brushes her hair in preparation for the morning while excitedly sharing with Riku the details of her blossoming romance with Dark. Her sister angrily suggests again that Dark might be a womanizer, but Risa defends the thief and insists that him not kissing her when he had the chance was the behavior of a gentleman.At the police headquarters, Satoshi emotionlessly greets his father in his office. Commissioner Hiwatari cheerfully returns the greeting with a hug and apologizes for not seeing him as often as he would like. Satoshi interrupts him when the hug becomes painful, and they continue to discuss work matters. Reports indicate that no progress had been made in the capture of Dark, but his father is confident that Satoshi will capture the thief eventually and they will be able to living together again. After Commissioner Hiwatari hugs him once more, Satoshi leaves, stating he has work and ignoring the man’s cheerful apologies. As his son departs, the smile disappears from Hiwatari’s face, replaced with an intense gaze.
Satoshi walks through the hallway of his school. Daisuke rushes up beside him, asks if he is alright since he has looked awful lately, but only receives a question and blank stare from Satoshi. As the bell is about to ring, Daisuke runs away awkwardly, feeling relieved that Satoshi appears to be feeling better. Satoshi stares after him silently.
In the firelit basement of the Niwa home, Emiko and Daiki Niwa express concern about the growing power of the artworks, still unmatched to those from forty years ago. He says it is only a matter of time until the White Wings appears in front of Daisuke, whom they do not believe is ready.
In between classes, Satoshi attempts to follow Daisuke down the hallway but is stopped and must brush off an underclassman who wished to profess her love. Meanwhile Daisuke searches through Satoshi’s records and is awed that Satoshi has already graduated high school and college. The aforementioned boy silently appears behind him, asking why Daisuke is so interested in him. Daisuke shuts off the computer and asks instead how the boy unlocked the door to the computer room. He leaps at his chance for escape when Risa arrives with a lunch bento for him.
Risa gives him the lunch outside the school, where they sit on benches. Daisuke is filled with joy that his dream is coming true, however his first bite leaves him speechless, much to Risa’s concern.
Satoshi examines the file that Daisuke accessed on the computer and resolves not to underestimate the boy.
Despite Daisuke’s reassurances, Risa knows her cooking is horrible and asks Daisuke to continue tasting it for her as she practices and improves. When he learns that she actually wants to make delicious food for Dark someday, Daisuke leaves despondently. Lost in his thoughts, he accidentally bumps into Satoshi and knocks down the trays that the latter was carrying.
Outside, Riku stretches for lacrosse practice and is surprised to see Daisuke together with Satoshi, as he had offered to carry half the trays.Below the gym, they enter the freezer. Soon, the door locks behind them, trapping them in a room filled with -20 degrees Celsius air. Their shouts and struggles are fruitless, and even Daisuke cannot hack the lock. Satoshi recommends they look for another way.
Risa searches for Daisuke in their classroom but finds only his bag on his desk.
The boys continue to freeze in the room. Satoshi suggests that Phantom Thief Dark would easily escape from this situation, but Daisuke does not take the bait, though he accepts the possibility in his mind if there is no other way. As Satoshi concludes that the other boy’s compassion will lead to destruction, his chest begins to ache. He falls against Daisuke, who attempts to soothe him. In his mind, Dark shouts for the boy to transform so he can beat up Satoshi and escape. Daisuke refuses the violent idea, so Dark warns him that Satoshi’s power is growing.
Satoshi apologizes for the embarrassing display and regains control. As they sit against the cold door, he silently surmises that “they” are calling upon each other at this inopportune time due to his and Daisuke’s proximity. Daisuke moves closer, suggesting they use each other’s body heat to stay warm.
When Daisuke asks why Satoshi attends the middle school despite having graduated, Satoshi admits that he wanted to live like an ordinary fourteen-year old. Daisuke’s outward relief at the response gives Satoshi another jolt of pain.
As the sun sets outside, Risa relays her worries for Daisuke to Riku and asks for her help.
Flinging Daisuke to the ground, Satoshi shouts that he does not need friends, especially one like Daisuke. Satoshi is shocked when the other boy does not understand, but the pain in begins to overwhelm him. One of Satoshi’s eyes has become golden and a bright light appears behind him while he struggles.
Dark stops Daisuke from rushing forward to help. The pain overwhelms Satoshi as feathers burst from his back and he rips his glasses from his face. Dark states that Krad is finally emerging. Satoshi’s finally head falls forward and white wings grow out of his back.When the bright light fades, a man with golden hair and eyes, and an ornate white outfit is standing where Satoshi used to be. Krad greets Dark, who orders Daisuke to transform immediately. However, the photo that Daisuke would have used to transform slips from his hand while Krad pulls out a white feather from his wing and attacks.
The Harada twins hear the resulting explosion, and Riku remembers that Daisuke brought trays to the storage room. When they arrive, the door is locked, but they can hear the bangs and Daisuke’s cries from within the freezer. Risa runs to get a teacher.
When Krad turns around from his destruction, he sees Dark crouching above, holding Risa’s photo. He attacks again, damaging anything that touches his glowing feathers. Dark chides the other angel for recklessly using his own tamer’s energy, but Krad remains unbothered; he will take Satoshi’s body as his own soon.Satoshi interrupts the battle, holding back Krad’s body from within and causing the white feather to dissipate. Dark takes the chance to attack, and their equally matched powers lead to a large explosion.
When Riku finally opens the door with the help of Risa and a teacher, Kaseda-sensei. She finds Daisuke unconscious and his clothes torn. He awakens and asks how Satoshi is. Kaseda, carrying the other boy on his back, says his back is damaged but there are no severe injuries.
The next day, Daisuke is late again to the tram, but finds Satoshi outside in front of a limousine, offering to give him a ride. In the vehicle, Satoshi explains that the incident in the freezer was classified as a refrigerator malfunction. Satoshi tells Daisuke that it would be best if they did not see each other for a while. Daisuke watches in front of the school as the limousine drives away with Satoshi inside.
- Krad is called by name for the first time in the series, and he also calls out Dark's name: Dark Mousy.
- Satoshi studied abroad after graduating high school at the age of eight, and graduated as valedictorian from Lagoon University at the age of thirteen. He joined the police headquarters immediately upon returning.
- The name of the university Satoshi graduated from, “Lagoon”, is an allusion to Lagoon Engine, another manga series created by Yukiru Sugisaki.
- “But with your ability, I believe it won’t be long. So hurry this up so we can live together again.” Comm. Hiwatari
- “I’ve been thinking a lot… And I think it has to be Niwa-kun.” Risa
- “Even though he acts dimwitted, he has already accessed most of my data.” Satoshi
- “He’s telling me to transform into Dark. No way… But if that’s the only way…” Daisuke
- “It’s only a matter of time. His kindness will only lead to his own destruction.” Satoshi
- “Daisuke, get out Risa’s picture! Transform into me so I can beat this guy up! And then I can escape from this hellhole!” Dark
- “Just like I’m inside you. Inside Hiwatari-kun, there’s him.” Dark
- “It’s been a long time, hasn’t it? Such an honor to see you again.” Krad
- “Krad, to abuse your tamer like that. Is that alright? … Behind your angelic facade lies a devil’s cruelty!” Dark