Her Relationships with:
Aki and Miki: The bond that ties these three sisters together is very strong, and they would hate to see anything bad happen to the other. When Neon was getting ready to use the Requiem, she encased them in these bubbles which would protect that from harm, since she wanted them to live. They were so disraught that they banged on the sides of the barriers, and screamed to be let out, saying that if she had to die, they wanted to die together with her. Luckily for all three of them, Recca managed to save her life and they were together again.
Once in the manga, when Aki was one of the judges, as well as Kuukai, during the final round of the Dark Martial Combat, Demi asked her what her opinion on Mikoto was. Aki replied "Neon doesn't like her, so I hate her too."
Kurei: Neon loves Kurei A LOT. She loves him so much that she was even willing to sacrifice her life just to get rid of his enemies (In this case, Team Hokage) for him! Soon, much like Raiha's "Proof of Love" page, I'll put up a section on which you can see how deep Neon's attraction to Kurei is, and why.
Even when he punished her for telling Recca about his past, she still remained devoted and loyal to him.
Raiha: I think she and Raiha are very good friends, as they are always seen discussing Hokage's opponents with each other. In the manga, when Neon wanted to join Uruha, she asked him for help and he warned her that the training would be very tough, but she stuck to it anyway and became one of the Uruha Group of Ten. Neon still doesn't know Raiha very well, though, and sometimes he surprises her by not acting really serious and knowledgable and not as his usual goofy self. However, Neon sometimes surprises him with her keen observations, especially if they concern Kurei. ^_^
Jishou: Neon, Jishou and Raiha seemed to be a trio before Jishou was killed. They could be seen training together, and although Jishou and Neon quarrelled alot, with Raiha acting as a peacemaker, they were probably really good friends since she was really disraught over his death at the hands of Magensha. Their strong devotion to Kurei is what strengthened the bond between this two.
Joker: Neon and Joker don't really interact very much, but I think that they're pretty good friends. Although Neon sometimes does get a bit exasperated when he says or does stupid things, or just acts his usual arrogant self. ^_^
Lately there's been lots of neon/Joker romance fics etc. floating around, but they're just for fun. :) Don't pay any attention to them; Neon and Joker are definitely NOT going to get together in the manga. It is, however, fun to imagine, so you should read those Neon/Joker fics (Most of the best are by Bottou-chan and Fuuko no Miko) and just enjoy them for what they are, stories which will never come true. (Much as some people would like them to) ^_^