Urameshi beated Hiei in their first meeting...Strange? Maybe, but this win was just luck...What Yusuke has in his life is luck anyway....
Their second meeting was when they fought against Suzako and the other youkais. Hiei told him that he would put the things in the right place after that problem, and that for now, he would help him because that demons had stealed some things from him...
When they are stopped by the Portal of the Treason, Hiei starts to be atonished by Yusuke's attitudes and trust in him after all he had done...
As the serie goes, Hiei gets kownledge of Yusuke's power and gets a great admiration for this.
He saved Yusuke's life when this was going to dye in Hagiri's hands...

Urameshi derrotou Hiei em seu primeiro encontro...Estranho? Talvez, mas foi pura sorte...o que Yusuke mais tem na vida é sorte...
O segundo encontro dos dois foi quando eles se juntaram na batalha contra Suzako e os outros demônios. Hiei disse-lhe que acertaria as contas com ele mais tarde, e que por hora estava junto porque os demônios tinham roubados alguns tesouros dele...
Logo quando eles entram e encaram o Portão da Traição, Hiei começa a ficar espantado com as atitudes de Urameshi, que confia nele depois de tudo o que ele tinha feito...
No decorrer da série, Hiei começa a perceber a força de Yusuke como guerreiro, e o admira por isso.
Chegou até mesmo a salvar a vida dele quando este ia morrer nas mãos de Hagiri...
 
 

This two are a serious fate....Since their first meeting, Hiei and Kuwabara started to cut each other with words, thing that always happen yet. But Hiei cares a little about Kazuma...Hn, it's truth that the thinks the other is an idiot, stupid and scandalous human, but still...
And Kuwabara, always saying that he hates Hiei's arrogance, will help the little youkai wherever he needs to...
 
 
 
 
 
 
 

Wait a little, please, I'm doing this part...but I KNOW Mukuro means something to Hiei...I just didn't want to put it before because I didn't know their story alright...but now that the series finished here in Brazil I can make something good for here...^^
 
 
 
 
 
 
 
 
 
 
 
 
 

She's Hiei's disappeared sister, who was rapted by Sakio and kept prisioner for years, because her tears (tear-gems) were very expensive to sell in the human-world. Some time later, she was stealed for another business-man and locked in the Ningenkai for the same motive.
Thanks to this, Hiei could sense her presence with his Jagan and went to rescue her. At the same time, Koenma sent Yusuke, Botan And Kuwabara to this mission, because they need to arrive before Hiei to stop him from killing the business-man (or Hiei would be condened for the Reikai, because an youkai can't kill an human.)
After Yukina was saved, Hiei decided to doesn't tell her that he is her brother, in order to protect her from the hard truth, since he was an murdered, cruel and cold. The people who know this truth is Kurama, Yusuke, Botan and Koenma. Kuwabara is the one that doesn't know anything about the hole thing...
But Hiei really didn't told her the truth because he didn't want her to suffer if he came to die in one of his missions. She would suffer just a little if she didn't know that he was her twin abbandoned.
Yukina spent all the serie tring to find her brother, and just at the end she discovers that he is Hiei. ( IMO!!!!)
By the way, she is one of the few people that has a considerable power against Hiei's heart...
Well, it was for her that he suffered the painfull operation to implant the Jagan!
 
 
 

Well, what can I say about this two?
Hiei knew Kurama when his human body was 14 years old... an year after, both of them started to fight together in order to steal the Reikai's treasures and some time after, in order to help Yuuuke and Kuwabara in their missions.
Kurama is the only person that Hiei truly cares in his heart, except for Yukina. We can see the little detals that say HOW MUCH Kurama means to Hiei. Both of them are always side to side, and despite the fact of both fight in a time of four people, they always seems to be by themselves. And is a bit hard to find both of them far from each other, until in the pictures...
And...hn...Kurama is the one that really knows Hiei in his soul, he can agree with this or not. And he is also the only person that knows BOTH faces from Kurama perpectly...
The few hours when we can see that Hiei almost lose the control of his coldness is when Kurama is fight or in dangerous. He doesn't say words but it's easy to see what he feels for that Youko...
If you still doubt of this, read a few fics about YYH...not only mine but the other good people who write...like Lalachan, WhiteCat, Korogi-san, Julie Farel, Katchan...^^