Elvis as a symbol
For young Elvis Oke, Elvis Presley is more than just a star or a hero; he is a deep part of how Oke perceives himself. He makes money busking as an Elvis impersonator, which is symbolic because he doesn't really look all that much like Elvis. The symbolic allusion makes the reader understand that in Oke's mind, he's the king. He knows that he doesn't look like much, but secretly, he suspects that his life is of the utmost importance. There is more to him than meets the eye.
The journey out of poverty
Because Oke knows he is a king in disguise, so to speak, he feels a pressing need to escape his life of poverty. There are some among them who are content in the lifestyle that Lagos entails, but Oke doesn't want to struggle forever. He sets his mind to escaping Lagos, but that's obviously easier said than done. This constitutes the major plot line of the story. When he leaves at the end of the book, the reader knows he has succeeded in other ways as well.
Redemption as a symbol
Redemption is a character who helps Oke to find odd jobs, usually illegal jobs. He helps Oke to make some extra money, raising interesting moral conundrums. Is it wrong for Oke to make a little cash on the side by committing crimes? He doesn't have many other options, obviously, but still, the dilemma is hard to face. The fact that this character's name is Redemption only adds to this strange moral conundrum.
Capture and containment
When Oke is kidnapped and abused by a child trafficking operation, this can be seen as a symbol. First of all, it symbolizes the existences of nefarious organizations like this which plague the third world in real life, unfortunately, but in a more abstract sense, the scene symbolizes Oke's emotions about his inability to leave the ghetto. He feels captured and tortured in his normal life. The battle for freedom is already the battle that shapes his character.
Sunday's death
When his father, Sunday, is killed by land developers and business men with construction teams, that is a clear sign that Oke is the victim of systemic injustice, because the people with authority in Lagos care more about making more money for their selves than they care about human life. They are treated without dignity, and the death symbolizes Oke's absolute victimhood, just in time for him to escape. Since he escapes, he can be seen as a martyr of poverty with an important story to tell.
