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.

Hajime for the most part views Kouki as a nuisance that he wants to avoid dealing with due to his naive mindset and troublesome habit of interpreting things to fit his worldview. It is due to these traits that Hajime decided not to reveal that the god Ehit who had summoned them to be heroes was a twisted Evil God that viewed living beings as playthings or the fact that Daisuke Hiyama attepted to kill Hajime, since Kouki's idealistic mindset would never allow him to doubt those who are praising him. Kouki bitterly acknowledged that he wouldn't have believed Hajime if he revealed the truth about Ehit.

After Kouki and his party joined Hajime's journey to conquer the remaining Great Labyrinths, Kouki's idealistic worldview and his desire to save everyone clashed with Hajime's more pragmatic worldview and his desire to prioritize returning home above all else. Kouki repeatedly attempts to impress his ideals onto Hajime or lecture him about saving the world. Kouki tends to try to interfere in situations where it seems that Hajime is at first reluctant to act and tends to disapprove of Hajime's more ambiguous actions such as helping the Haulia defeat the Empire. While Kouki is initially confident that he can easily clear a Labyrinth and become as strong as Hajime, he discovers how wide the distance between their strength is. Kouki is reluctant to accept help from Hajime so much so that he initially refuses to use the new abilities of his Holy Sword that Hajime added due to the fact that he wants to prove he is stronger then Hajime.

He eventually snapped after seeing Shizuku with Hajime together and finally noticing her growing affection for the latter. During the final trial in the Frost Caverns of Schnee, he was forced to confront his worst personality traits in the form of a doppelgänger, 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 caused 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 companions to get what he wanted 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 but kept his warning if he kept bothering him and his friends (harem), he will kill him just like he did with Daisuke. After waking up and calming down, Kouki felt bad about how he attacked Hajime. However, he still couldn't accept Kaori 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 felt he couldn't match him; because of the difference in resolves between them. After seeing Hajime's memories, while he sympathizes with Hajime's desire to return home, Kouki still maintains that Hajime has stolen everything from him and thinks that he is not mistaken in his beliefs.

In the After Story, Kouki has trouble sorting out his feelings towards Hajime as due to his past actions, Kouki cannot bring himself to be angry at Hajime but rather disappointed at himself for being indecisive and not strong enough to realize his ideals. When the "Dark Being" attacked, he thought about asking Hajime to transport the "Dark Beings" to another world, so that the people of Synclea Kingdom could be safe and the "Dark Beings" could survive without harming others. He was reminded of Hajime's way of prioritizing those close to him when he heard Koone's wish to save her sister above all. When Kouki was about to escape from Arquette that was attacked by the Dark "Beings", he though how he wanted to meet Hajime again along with his family and friends. After defeating the "Dark Beings" that were attacking Arquette, Kouki resolved himself to fight for the sake of what he believed while accepting everything in contrast to Hajime's view of dividing the world between enemy and ally. Kouki and Hajime finally reunited when Kouki was about to be attack by a pack of "Dark Beings", as Hajime dispatched them. Hajime then asked Kouki to go back with but Kouki refused as he wanted to save Moana. Thinking that his hero complex has returned, Hajime said that he would call Shizuku to give him a lecture but Kouki resolved himself to stay to save Moana. After the rest of Kouki's friends left the decision of Kouki's retrieval to Hajime, Hajime wanted to confirm if Kouki thought that his choice was correct to him, to which Kouki responded that such a thing didn't matter, a answer which impressed Hajime. Hajime went to defend Arquette so Kouki could save Moana as he sent Kouki off with the aid of griffon Grim Reapers. When asked by their friends why Hajime lent Kouki his aid instead of dragging him back, it is revealed that Hajime was curios as to where Kouki who has obtained a answer which is the opposite of Hajime is going to end up. After helping defeat the "Dark Beings", Hajime was willing to grant Kouki's request of taking Moana with him.

Ryutarou Sakagami
Ryutarou is one of Kouki's closest friends. Kouki and Ryutarou have known each other for a long time and have a deep bond. Kouki knows that he can always count on Ryutarou to support him and Ryutaro will always try his hardest to stand by Kouki and his friends to try to help them. While the two have a good relationship, Ryutarou is secretly jealous of Kouki due to Ryutaro being weaker then Kouki and due to Kouki being percieved as a main character who gets all of the fame and women to fall for him compared to Ryutarou who is just there to support the main character.However despite this jealousy, Ryutarou still cares for Kouki and genuinely sees him as his oldest dearest friend and desired to obtain enough strength and power "beat some sense back into him" when he began to lose his way.

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. Later upon mentally hitting his breaking point in the final trial of the Frost Caverns of Schnee battling his doppelganger, Kouki came to the delusional and convenient conclusion that Kaori did not truly love Hajime, but was instead "brainwashed" by Hajime into loving him. He later brazenly proclaimed that she along with Shizuku "belonged" to him due to their childhood friendship, that he interpreted as romantic love, causing him to try and kill Hajime to "free" her. However, Kouki hurt Kaori's feeling as goes as she slapped him in the face and caused her to be angry and sad for his so-called "righteousness" of failed attempts on killing Hajime following his defeat by Hajime. After he gave up his attempts of killing Hajime, Kouki now no longer fell in love for Kaori as he now fell in love for Queen Moana de Shelt Synclea as he finally accepted that Kaori was truly in love with Hajime and would not return his affections.

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. Shizuku usually meditated the conflict between Kouki and Hajime as Kouki usually clashed with Hajime's choices during their travels. Later upon realizing that Shizuku also bared romantic feelings for Hajime, Kouki could not believe nor accept it, as he had believed that Shizuku promised to never leaving him when she agreed to look after him and the rest of the hero party. This caused him to delude himself into thinking that Shizuku was in love with him, eventually causing him to conveniently interpret this situation as Hajime "brainwashing" her to love him, leading him to willingly attack and fight against Shizuku in order to "save" her and was even willing to resort to extreme, possibly fatal force to accomplish this. However, despite this violent behavior, Kouki still saw her as a friend and promised to help her recover after defeating Hajime and "freeing" her from Hajime. Later upon being defeated by Hajime, Shizuku clarified that she does indeed love him, but not in the sense as a lover, but something akin to a troublesome younger brother, once again repairing their friendship. However, Shizuku made it clear she wasn't asking for his blessing in regards to her feelings for Hajime and was simply telling him because he's her childhood friend.

Eri Nakamura
Eri see's Kouki as her savior and will do anything for him to be her's. Eri has harbored an obsession with Kouki ever since he saved her from commiting suicide to escape her abusive mother. She has harbored love for him ever since that moment and was thrilled to come to Tortus where she had the opportunity to make Kouki hers. During Cattleya ambush of the Hero party, Eri was willing to sacrifice all of her classmates if it meant that she and Kouki would be safe. She later betrayed the Heiligh Kingdom and her classmates to the demons if they promised to spare her and Kouki. Kouki was at first unwilling to believe that the kindhearted girl he knew would betray him and his classmates but was forced to accept reality after Eri revealed her schemes and was forced to accept the truth when Eri retreated with Freid and Aiko revealed Ehit's nature as Evil God. When Kouki snapped at the Frost Caverns of Schnee, he though Hajime had "brainwashed" Eri as well, believing he was the reason why she betrayed them.

Ehit
Ehit had chosen Kouki to be a potential vessel thus blessed him to be the strongest out of his summoned Heroes by giving him the Job Class of Hero as well as having the highest stats and most amount of Skills out of his classmates. Kouki due to his misguided sense of justice and inability to differentiate between good and evil proved to be one of Ehit's easiest to manipulate pawns, having trained hard in preparation to participate in his war, even attempted to recruit Hajime's extremely powerful party members, Yue, Shea and Tio to joined him in fighting for Ehit. Hajime even stated Kouki will never want to believed that Ehit whom the Humans had worshiped and had also specially chosen him to be the Hero is in reality an Evil God and all his efforts in fighting for Ehit are meaningless and would even get angry at Hajime for supposedly villianize Ehit, a fact which Kouki could not denied. However, after learning from Aiko of Ehit's true nature as an evil god and his manipulative schemes of using him and his classmates as pawns for his game of death including the fact that Eri had personally exposed how Ehit had helped her in betraying them by sending Noint to abduct Aiko and brainwashed King Eliheid and his nobles during her death trap, Kouki despite his misguided sense of justice, begrudingly forced to accept the truth of Ehit's evil nature and thus lost any respects for the God in his atrocities.

After being told by Hajime that he has no desire to save the people of Tortus from Ehit's manipulations, Kouki affirmed that he would save Tortus by obtaining the power of Ancient Magic to defeat Ehit and demanded that Hajime take the Kouki and the rest of the Hero party with him to conquer the last remaining Labyrinths.

Ehit revealed that he summoned Kouki as a pawn in his game to balance the board by helping the human side since Freid obtained the power of Ancient Magic. He also had plans of making Kouki his host body before he rediscovered Yue.

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 Synclea Kingdom that Kouki is summoned to in order to save her people from a race of creatures called the "Dark Beings". Moana quickly establishes a friendly relationship with Kouki who is the hero that Foltina summoned even asking him to call her casually with he is reluctant to do at first. Moana notices that Kouki is struggling with some internal conflict as they discuss what it means to be a hero as she later apologizes for forcing Kouki to kill for the first time, seeing as it traumatized him a bit. She acknowledged his kindness but Kouki vented his feelings self-loathing as he told her that he is scared of himself as he cannot trust his own judgement. When he heard how she risked her life in a climatic battle against the "Dark Beings" while straining her health to protect her kingdom, Kouki stated that he admired her. When they were staying the capital, they discussed their motivations and reasons for fighting, thus growing closer as Moana stated that the two of them are the same since they want to keep fighting for the sake of others no matter what happens to them. After Kouki stays behind to defend Arquette, Moana rallies reinforcements to support him as she would not let him die while he was fighting for her kingdoms sake. When she witnesses Kouki, who was nearly fatally wounded as had cut down several thousand Dark Beings for the sake of of protecting the people of Arquette, she became tearful. As Kouki was recovering from his injuries, Moana hugged him as she was relieved that he survived. When Kouki told her that he had found his answer, Moana promised that she would support his choice no matter what it was as she wanted to become his strength, as Kouki started calling her by her name and talking to her casually. After witnessing Lillin kiss Kouki on the cheek, Moana momentarily wanted to push down Kouki, who still could not move. When Moana attempted to confront the "Dark King", Kouki was able to come to her side, rescuing her and defeating the "Dark King" thus ending the threat of the "Dark Beings".

Moana decided to accompany Kouki back to Tortus, where she adventures beside him while engaging in catfights with the Goddess that also fell in love with Kouki.