The following is a description of the Orc Leader's relationships and interactions with other characters in Monster Musume: Everyday Life with Monster Girls.
Humans[]
Kimihito Kurusu[]
The Orc leader has never directly interacted with Kimihito during the series, but from the news in Chapter 11, Kimihito knows about the P.O.R.K's raid on the shop Libido Doujin, which is why he views the Orc Leader as a creep and someone to avoid. In Chapter 40, when the Orc Leader attempted to grope Liminal women on the street, Kimihito threw the tied up Lilith at the Orc leader, forcing him to let go of the transformed Doppel, hiding from the Orc along with the real Lilith; Kimihito was also there later when the Orc leader was arrested. The Orc leader was unaware of Kimihito's interference in his criminal acts, as he had not actually acknowledged Kimihito.
Kuroko Smith[]
As a coordinator of the Interspecies Exchange Program, Ms Smith is an enemy of the Orc Leader. In Chapter 11, the two interacted for the first time as Smith together with the M.O.N. arrested the P.O.R.K after they raised the Doujinshi shop and commiting a hostile situation. Because of his sneering arrogance, the Orc Leader seem to take Ms Smith seriously after he voluntarily surrendered, even mocking her. However, after she seemingly shoothing him with the rubber bullets, the Orc was briefly shocked as the Interspecies Exchange Bill forbade a human from harming a Liminal, although it turned out quickly that the "Smith" who had shot him was actually Doppel in transformation.
Later in Chapter 84, Smith encountered the Orc leader again, although he was quickly defeated by Aluca, Garu and Vikk before he could detect Smith's presence. It is also revealed that even after being deported from Japan twich (in Chapter 11 and Chapter 40) by Smith, the Orc leader threatened her that he would come bacck, showing that he is not intimidated by her.
Bicycle Police Officer[]
The Orc leader hasn't interacted much with the Bicycle Police Officer, but since they're on different sides of the law they're not on friendly terms. At the end of Chapter 40, the Bicycle Police Officer arrested the Orc leader for his attemped attacks on Liminal women on the street, although the Orc leader didn't fully realize this as he was still too dazed from the shock of Doppel's traumatic transformation.
MON[]
Zombina[]
As a member of the MON, Zombina is an enemy of the Orc leader. In Chapter 11, after Zombina sneaked into the libido shop and the Orc leader became aware of her through his sense of smell, he shot her several times in her stomach with the intention to kill her, sadistically taunting the police that this was "self-defence", because Zombina allegedly violated the Extraspecies protection laws through her attempted ambush. The Orc leader didn't notice that Zombina was a Zombie, which is why he, like the other Orcs was quite surprised when she revealed that she had just been "playing dead" the whole time.
Tionishia[]
The Orc Leader hasn't interacted much with Tio, but as a member of the MON, she is an enemy of him. In Chapter 11, Tio helped arrest the P.O.R.K with the Orc leader also seeing how Tio knocked two of his Orcs unconscious. Despite this, the Orc leader doesn't seem to have personally paid much attention to Tio, although he probably doesn't underestimate her due to her strength which surpasses even his own.
Manako[]
The Orc leader hasn't interacted much with Manako, but as a member of the MON, she is an enemy of him. In Chapter 11, Manako used her rifle to destroy the guns of the Orcs, with the Orc leader was visibly shocked as he realizes that since he had not smelled any weapons, the shots had been fired by someone who can hit a target from more than a kilometre away, and the Orc leader wondered how anyone could accomplish such a feat. It can be assumed that the Orc leader also found out that Manako was the sniper because she was praised for her feat by the other MON-girls in the libido store before they arrested the P.O.R.K.
Doppel[]
Because of her work at the MON, Doppel is enemies with the Orc Leader and in fact, of all the members of the MON team, she has the most personal enmity with the leader. After the P.O.R.K took over the Libido Doujin shop in Chapter 11, Doppel took on the role of decoy to distract the Orcs by taking the form of a helpless young girl. The plan worked because the Orcs were so distracted by Doppel that they are overwhelmed by the other MON-team members one by one. However, the Orc leader had already groped Doppel at bit at this point, which of course she resented him very much.
Later in Chapter 40, when the Orc leader illegally entered Japan again, Doppel tricked him into chasing after her through his lolicon complex by taking the form of the childlike Lilith. The Orc leader immediatelly fell for it and chased after Doppel and briefly managed to capture her, although Kimihito's intervention prevented him from harming her. After a few moments of confusion, the Orc leader finally remembered his previous encounter with Doppel, but even that could not save him from the horror of the terrible transformation that Doppel was transforming into before his eyes. This traumatized the Orc leader so much that he became afraid of little girls afterwards.
TALIO[]
Liz[]
The Orc Leader has not directly interacted with Liz, but since they are on opposite sides of the law they are enemies. In Chapter 40, TALIO was given the task of arresting the Orc Leader for his illegal entry into Japan again, although in the end the criminal was defeated by Doppel and Kimihito and handed over to TALIO, although the Orc leader didn't fully realize this as he was still too dazed from the shock of Doppel's traumatic transformation.
Kinu[]
The Orc Leader has not directly interacted with Liz, but since they are on opposite sides of the law they are enemies. In Chapter 40, TALIO was given the task of arresting the Orc Leader for his illegal entry into Japan again, although in the end the criminal was defeated by Doppel and Kimihito and handed over to TALIO, although the Orc leader didn't fully realize this as he was still too dazed from the shock of Doppel's traumatic transformation.
Monster Community[]
Pioneer Orc Renaissance Kinsmen[]
The Orc leader was originally the leader of the P.O.R.K and their mutual relationship seemed to be based on respect as he never called them out for incompetence while the other Orcs referred to him as "boss". When the Orc leader tried to grope the disguised Doppel, the other Orcs said that it was unfair that he had the girl just for himself, and he was actually willing to allow his group to grope Doppel as well. However, the Orc leader never showed any direct concern when the other Orcs were incapacitated by the MON-team, and it is unknown whether he has had any contact with them since the incident in Chapter 11.
Draco[]
In Chapter 40, while searching for a victim on the streets of Tokyo, the Orc leader attacked Draco after noticing through his sense of smell that she was a woman and attempted to grope her. However, Draco was just a random victim as the Orc leader found her a bit "too old for his taste" due to his lolicon complex. That's why he immediately lost all interest in her when he saw Doppel in the form of Lilith, as her childlike appearance was much more in line with his perversion.
Lilith[]
The Orc leader has never properly interacted with Lilith, but when Doppel changed her form into that of Lilith in Chapter 40, the Orc was immediately perversely attracted to her due to his lolicon complex, chasing after her and attempting to sexually molest her. He actually caught her, but Kimihito then threw the real tied up Lilith at the Orc so that he had to let Doppel go. The Orc leader was confused to see Lilith twice, but Kimihito was able to use the moment of confusion to hide with the real Lilith. This in turn gave Doppel the opportunity to shock the Orc leader to his core with a terrifying transformation.
Aluca, [[Garou & Vic
The Orc leader and the three Liminal girls are enemies. In Chapter 84, when the Orc leader tries to cause trouble in the Onsen of the Hotel Okaya, Vic, Aluca and Garou worked together as a team to stop him. Vic turned off the lights in the hotel and Aluca and Garou attacked the Orc together with Aluca injuring his nose, whereby he was no longer able to orientate himself in the dark with his sense of smell, while Garou gave him a good beating, whereby she also knocked out several of his teeth. The Orc leader was completely taken by surprise by this attack and collapsed unconscious before he even had time to really realize who or what had attacked him.