"I love you brother, but I can't be on your side about this one. Fear might have rushed my hand, but your decision was selfish and arrogant."
Relationship: "Brother", Friend?, Enemy?, Former leader
Chrono's relationship with Aion is complicated. They were nearly inseprable as kids, but now Chrono can barely stand to be around him. He craves Aion's approval of him, but at the same time is desperate to assert his independence from him. He believes that Aion has good intentions, but doesn't trust Aion to make good moral choices. He does love Aion, but he's prepared to kill him if he has to do so to protect Mary, and knowing that he could be capable of it frightens him. All in all, he can rarely talk to Aion without starting a fight these days...but that doesn't stop him from trying anyway.
Relationship: Fellow Sinner, childhood friend
Viede is a Sinner from Chrono's world. They grew up together and Chrono considers him a friend, although he doesn't feel as attached to him as he does Aion. That being said, he also trusts Viede to be more reasonable than Aion. Chrono often worries that Viede will turn on him if he finds out about Chrono's betrayal, since he's aware of the other demon's devotion to their "King".
"The only people who can be happy are those who believe they can be happy. If I believe there's a sky more beautiful than the one today, then I'll keep searching for it until I find it."
Relationship: Friend, potential meister
Chrono's always been drawn to strong personalities, so Takuto's ~*~DAZZLING SOUL~*~ had him tagging along with the Galactic Pretty Boy before he even knew what was happening. He finds Takuto's philosophy on life inspiring, although he can't help but wonder how realistic it really is.
"Stop doubting yourself! You want to move forward, don't you?"
Relationship: Friend, potential meister, inspiration
Kaoru is another one of those people with strong personalities. Since almost the first day he arrived she's constantly reminded him of his desire to protect people, and encouraged him to use that desire to help him fight. He's not sure what to do with a seemingly "delicate" girl that has so much physical and emotional strength, but he definitely knows that he admires her and wants to live up to her expectations of him.
"Humans fear what they cannot understand. And that is everything that is different from them."
Chrono met Demona when he volunteered to help on the tour for new guests. He's curious about her people, Gargoyles, since she looks a little like a demon, although he finds her rather grumpy. Still, she has reason to be. Her mistrust of humans worries him a little, but she didn't seem too hostile when he mentioned he had a good friend that was a human...so...her intentions MUST be good, right? ...Yeah, Chrono's not the best judge of character.
Coding from here with some mild editing.
Important canon relationships (that aren't in the game):
Mary Magdalene: A holy seer that Chrono captured for Aion and ended up falling in love with (not that he'll admit it out loud). When she was possessed by Pandaemonium, Chrono refused to kill her, which caused him to leave the Sinners in a desperate attempt to save her. He was traveling with her to the Order when he was brought to Death City.
Pandaemonium: The name of both the demon's world, and their Queen. Pandaemonium is the mother of all demons (including Chrono) and has a strong power over them. Chrono doesn't understand her much beyond what he's been told.
Genai: One of the Sinners. Genai is probably the Sinner Chrono gets along with the least--they clash because of Genai's crude personality and Chrono's sensitivity.
Rizelle: Another Sinner, one who is in love with Aion. Chrono doesn't seem very close to her, but isn't outwardly hostile either (although he later shows distaste for the manipulative nature of her powers).
Shader: A Sinner, and probably the one that Chrono's the closest to (other than Aion). Chrono's never sure how to handle her hyperactive personality, but he appreciates how caring she is toward others and is pleased that she seems to like humans as much as he does.
Ewan Remington: At this point in time, Chrono doesn't know much about Remington other than that he was Mary's guard. The boy's piercing eyes and apparent hatred of demons has stuck in his mind.