Goblin Slayer deeply loved and respected his elder sister, saying that she never failed at anything. Her death greatly affected his psyche, haunting him to this day.
As Goblin Slayer lays still observing Goblins, he recalled his sister telling him that "Observation" was one of a Hunter's most valuable skills, and that his father was very good at blending in.
Burglar was the one who saved Goblin Slayer's life when he was still a boy, bringing him back to a cave where he was trained. He taught him basic combat, assassination, scout and everything related to mass murder of an entire nest. Burglar loved to recite poems and riddles whenever he gave him hellish training to make Goblin Slayer more disciplined. He also taught him to be an independent person, which Goblin Slayer cited that he didn't teach him to become a party member.
Priestess was the first party member of Goblin Slayer to work alongside him. They met when he saved her from being raped and killed by goblins. He tried to dissuade her from accompanying him, knowing it would be dangerous, but she followed regardless. He tries to make sure that she doesn't die during missions by teaching her everything he can to survive, as he felt guilty when Priestess was seriously injured by a goblin champion.
At first, Goblin Slayer wanted nothing to do with the archer and the other adventurers she came with in regards to a great war, but decided to let them join his party upon knowing they were hunting goblins. Goblin Slayer teaches the archer about how to handle goblins, much to her disgust. He gets flustered with how the archer highly restricts his methodology of dispensing goblins, so he improvises to respect her wishes; which becomes more frustrating the more extreme the situation is. Like Dwarf Shaman and Lizard Priest, he has grown to care for her and even consider her and the rest of the party friends.
Goblin Slayer and Dwarf Shaman are party members. Goblin Slayer trusts in Dwarf Shaman's spells in combat.
Goblin Slayer and Lizard Priest are party members. They fight side by side a majority of the time and are on good terms with each other. Lizard Priest is even more willing to help out Goblin Slayer if he is offered cheese in return.
Goblin Slayer was best friends with Cow Girl when they were kids. By chance, they reunited as young adults and the elated girl allowed him to stay with her and her uncle, where they continue their friendship.
Despite the trauma he suffered and years of separation, he still cares deeply for her well-being in his own way. This was seen when he makes traps around the house to prevent goblins from attacking and defended her uncle's farm from goblins while she was thankful for his care for her safety. She is also pleased that he is opening up to her more with his new friends and finding it nice that he is taking it easy in his hunts.
Guild Girl is one of the few people who is not put off by Goblin Slayer's personality and mannerisms. She also supports his hunting of goblins as she recognizes how dangerous they truly are. In return, he cares for her and is willing to protect her, as he killed Rhea Scout when he attacked her and felt guilty for playing dead in order to do so. He has accepted requests from her that did not involve goblins, including acting as an observer during a promotion exam and going on a date with her during the festival.
He is unaware that she holds affections for him but tries his best not to annoy her, as she can react quite menacingly when he does. Knowing Guild Girl has done a great deal for him, she has earned his trust.
Goblin Slayer is not starstruck by her reputation like other adventurers and only sees her as a client.
Sword Maiden eventually confesses her feelings for him but Goblin Slayer replies that he cannot understand them. However, he proclaims he will always be there to kill goblins for her, even in her dreams.
Goblin Slayer respects Spearman as a fellow adventurer, but is completely unaware of the latter's jealousy of how close he is to Guild Girl.
He has admitted to Spearman that he is the most trustworthy acquaintance he ever had.
Goblin Slayer and Witch seem to be on friendly terms. When he needed to set the destination of a Gate Scroll, he went to her for assistance and she provided them with no problem.
Like Guild Girl, she is one of the few people who is not put off by Goblin Slayer's personality and mannerisms.
Due to his dark past and trauma that saw all his loved ones killed by Goblins, Goblin Slayer is obsessed with killing as many goblins as possible, including varieties such as Hobgoblins and Shamans. Upon meeting Priestess, he admitted to believing there was the possibility of a "good" goblin, but ultimately stated that the only "good" goblin was a dead one.
Goblin Slayer has no noteworthy relation or interest in Ogre. Ogre was simply an unexpected addition to his job. Goblin Slayer did not regard Ogre as a noteworthy opponent before killing him; he taunted that even mere goblins posed a bigger threat.
Upon meeting Dark Elf and hearing his introduction, Goblin Slayer proclaimed no interest into who Dark Elf was, taunting that the Goblin Lord was more troublesome than him.
Due to his obsession with goblins, he holds no interest in them.