Kouki Amanogawa/Relationships

Hajime Nagumo
At first, Kouki considers Hajime a bother, viewing him as constantly fawning over Kaori due to his convenient interpretation of her attitude towards him. Later, after their reunion in the Orcus dungeon, seeing him becoming stronger and surrounded by many girls along with Kaori, who eventually decided to follow Hajime, he became jealous of him. This also coupled with fact that both of them have different way of thinking. After being saved twice during the attack on the kingdom, rather than being grateful, he became even more jealous of him. Kouki was further upset that despite his immense power, Hajime didn't believe he need to uses his power for "justice" because that's not what he wants.

He eventually snapped after seeing Shizuku with Hajime together and finally noticing her growing affection for the latter. During the final Trial in the Great Schnee Labyrinth where he was forced to confront his worst personality traits in the form of a doppelganger who encouraged these self satisfactory delusions and taunted him further in his failures, shortcomings and his inability to see things for what they truly are. This eventually causing him to lash out instead of accepting and conquering these negative feelings and aspects of himself and acknowledging them, choosing to believe that Hajime was only a monster who brainwashed not only Shizuku, but all his other companion to get what he wants in order to better fit into his delusional world view. While Hajime was annoyed by this, he chose to not to kill Kouki because it would have made Kaori and Shizuku sad.After waking up and calming down, Kouki felt bad about how he attacked Hajime. However, he still couldn't accept Hajime or Shizuku's feelings for him.

While Hajime and Yue were creating the Crystal Key to bring them back to Japan, Kouki and the others experienced what Hajime went through when he fell in the Great Orcus Labyrinth. Witnessing the pain, suffering and loneliness Hajime went through and his determination to return home, Kouki finally realized where Hajime's immense power came from and understood why he couldn't match him; because of the difference in resolves between them.

Ryutarou Sakagami
Ryutarou is one of Kouki's closest friends.

Kaori Shirasaki
Kaori is one of Kouki's closest friends. Kouki has always respected Kaori for being a kind person. But due to his denseness, he never notices that Kaori loves Hajime and thought she felt bad for Hajime who is always alone. More than once, he doesn't realize that what he says hurt Kaori more than help her, such as after Hajime falls into the abyss. When Kaori confesses to Hajime and declares that she would be going with him, Kouki couldn't accept it or believe that she really loved Hajime the whole time.

Shizuku Yaegashi
Shizuku is one of Kouki's closest friends. They have known each other for around 10 years and are usually seen together. However, unlike Ryutarou who blindly supports Kouki, Shizuku usually try's to get Kouki to think before acting. At times, Kouki will open up about his feeling to Shizuku, but to his dismay, she tends to point out where he's wrong rather than tell him what he wants to hear. After Kaori decided to travel together with Hajime, he plead Shizuku not to leave him, which she doesn't promise.

Eri Nakamura
Eri see's Kouki as her savior and will do anything for him to be her's.

Meld Loggins
Meld pays special attention to Kouki due to the later's vocation of "Hero". He would begrudgingly prioritize his safety over the safety of the other students. After the fight against Cattleya in the Great Orcus Labyrinth, Meld apologizes for not teaching Kouki that he will have to be ready to kill his enemies when the time comes, a mistake that almost cost Kouki and the others their lives because Kouki failed to bring himself to kill the demon when he had the chance. When Eri later uses Meld as one of her undead soldiers, Kouki was shocked and sadden to see what had happen to his mentor. Despite knowing Meld was already dead, Kouki couldn't bring himself to strike him down and end up hesitating too much.

Moana de Shelt Synclea
Moana is the Queen of another world that Kouki is summoned to in order to save her people from a race of creatures called the "Dark Beings". The two of them develop a mutual attraction for each other, and she now accompanies Kouki on his journeys in Tortus.