Jin and Izayoi had a rough start. Izayoi did not recognize Jin as a leader and simply a incompetent lad, though the boy admired Izayoi for his strong Gift. However Jin became furious with Izayoi to the point he was ready to kick him out of the community as the problem child has used Jin's name to declare that the [No Name]s wuld take out all the Demon Lords. However, hearing Izayoi's sound judgement and logical way of thinking, Jin grew a newfound respect for him. Now Jin often consults Izayoi for important matters such as the vetting of the main points to be brought up in the negotiations. Izayoi often calls Jin O-Chibi-sama (See Trivia).
Jin is like her little brother whom she just cannot stop worrying about, to the point where she was scolded by Izayoi for having so little confidence in her own leader. Jin relies on her the most when he needs someone to catch the problem children who have gone to create trouble again.
Jin respects Asuka for choosing to stay with the nameless community instead of going to a new one when offered the opportunity. As such he tries to support her in anyway he can
As with Asuka, Jin tries to support You and respects her for choosing his community over [Fores Garo]. He interacts with her on the same level as Asuka, but his admiration for her ability to fight is genuine.
To Jin Leticia is an important friend and comrade. The moment he learned that Leticia would be offered in a Gift Game he sought out ways to try and save her.
Jin's childhood and closest friend. She does her best to support Jin after he was made the new leader.
Jin's childhood friend and Leader of [Salamandra]. Sandora is very close to Jin and used to bathe together, as she reminded him of their past and wanted to repeat it again in volume 6. Though it was sternly rejected Jin had no choice but to accept. While he respects her status he still will cut her off during the negotiations if she happens to endanger them with careless though, albiet with logical words.
Jin summoned her back to Little Garden in Volume 3 during the Battle against the Titans. Originally Jin wasn't much to Percher, but he cared enough and was able to get through to her closed off mindset. At the end of Volume 6, she finally became close to Jin and even said that it wasn't fair for Jin to promise to help her achieve her dream when he had so many more problems to work out first.
Jin was originally welcoming of Highness for being a friend of Sandora, but once Percher implied she had met him before, Jin became wary of him.
As a friend of Sandora's, Jin was pleasant to her until he learned Percher was involved with Highness. Just as with him, Rin became a source of suspicion for Jin. In the end though he tried to reach out to the girl, offering his help.
Jin despises him, not just for the harassment but for also what Galdo has done to order to win Gift Games against others. He was more than willing to join in the Gift Game against him and felt no remorse that Galdo was being used by a then unknown benefactor and killed.