I realized this section with all my love, because the relation with the major characters are very important to understand Orcelito's personality, so I treat them in order of relevance for him: Family (BELCA - HECTOR - MUSCA) and partner in crime (KILIKO LAGEN).

ORCELITO & BELCA

Orcelito and Belca are half-brothers, because of Belca's mother, that's different than the one of Orelito. Their relation is my favourite from the series and I think that their bond is so solid that nothing can destruct it.
Orcelito is sweet with Belca, he knows that when he's with him, he can let himself cry. He doesn't need to pretend with the beloved brother, Belca is important for him not only like a brother but as his best friend.
Usually Orcelito secretly falling down from the window of his room in order to reach Belca's room, and the scene is always funny, because when Orcelito is alighting with his sheet, Belca is always down and looking at him, Orcelito precipitates near him! XD Another esilarant scene is when Belca shows him the porno papers that Hector gave to him, Orcelito's red face is so cute! XDD
Belca always thought that Orcelito and Hector are totally different, but many times he says that Orcelito reminds Hector, because of his love and devotion for the country.
But their personality are totally different and Belca understands this when after left the caste, he turn back it, thinking that Orcelito could be druged by Kiliko.
But Orelito is always the same, and Belca doesn't know

ORCELITO & HECTOR

Orcelito loved Hector. After his death we can realize that their personality share a thing: the consideration of the Amontel Popular.
Belca hates them, but Hector said that they're not monster, they're like humans, so they can feel pain and sadness. Orcelito thinks the same thing and for this reason his dream is realizing the propose of the brother: creating a place when all can be happy, humans or Amontel they could be. Obviously, as the kind person he was, Hector loved Orcelito (and as a big-brother, a lot of times treat him as a child XD). They're two brothers and their relation is usual in a family, but Orcelito never loved porno magazines of the brother. XD

ORCELITO & MUSCA

Orcelito is loved by Musca, and obviously, he adores his sister.
He's always kind with her, involving as a perfect brother, but she's fickle initially she doean't like Belca because of his origins.

So Orcelito can't accept this absurd situation and when Musca says that Belca is an usurper, Orelito hits her! XD I love that moment, he'll never leave that someone could insult an innocent person, especially if this one is a brother that is a good boy!

Even if initially Musca doesn't agree, day by day she understands that Orcelito is right. She loves him very much and she goes away from the castle in order to helps and save him, understanding that Orcelito became distant for some reason she can't know. His eyes are cold and she can't believe that that boy is him.

When Eco says her that Orcelito could be dead, she can't believe him and always in her heart, she prays for the brother. Her reaction is of tears and screams, her beloved brother MUST BE alive!! And even if she's just a child, she fights with all herself for his sake, isn't she cute?

Musca is a child but her love for him is infinite! :)

ORCELITO & KILIKO

Kiliko is the one that proposes to Orcelito to became a puppet of the gouvernament, if he doesn't agree, they'll kill him.
Obviously, after Hector's death, and after knowing that the gouvernament is convicted of that murder, Orcelito finds the thuth alone. Even prisoner, he's very able to escape from the window of his room and to unchain himself, so, consulting his beloved books, finally he realize that all the hate for the popular of the Amontel is a lie, they're not monster, they're experiments of the gouvenament that now want to have the power of the Royal Family.
Knowing it, Orcelito says with Kiliko and proposes him a blood path. He won't become the puppet of the gouvenament, and he won't die. He'll become king and I'll save the country, even, he'll do a big part of power to Kiliko, more than his father promised him. Kiliko hears Orcelito's words and he accepts the path.
Orcelito's strong personality is awesome, he can persuade who he wants with his words.
He understands that this is the moment to become cold and distant from the family, to protect them and to obtain the power to preserve the path with Kiliko. Kiliko likes him, he thinks that Orcelito is smart and resolute, and even braming power, he wants to know if Orcelito will be able to mantains the promise and to save the country. They share a lot of yaoi scenes, many times Kiliko is just a sort of servant. XD