Personality

Hibari is not exactly the most complex of characters. The best part about him is that he has nothing to hide - he is completely one hundred percent himself all of the time. For the most part, Hibari conveys his desire to fight - and he doesn't discriminate on who he will "bite to death." He desires to fight the strong and is intrigued by those with battle prowess - though this isn't to say he won't settle for fighting with anyone on the streets. When he isn't fighting or showing how much he wants to fight someone, he is generally just bored. Before he became involved with the Vongola family, he would frequently be seen yawning or sleeping. Even when conversing with his "allies" or opponents before a battle, he is still yawning and finding himself bored by it, rushing along the conversation to get the fight started. Honestly, we mostly just see him exhilirated in battle.

In the latest chapters, we have begun to see more of his personality show through. As seen above, there is a battle in the Curse of the Rainbows Arc between Hibari and the Varia. Mammon has used his skills as an illusionist to injure those fighting should they ever lose confidence in their victory. Here we see a rarity - Hibari becomes encased in ice and has an attack aimed his way. The illusion affects him and begins to injure him as he loses confidence in his ability to win this battle. This is probably a side of Hibari we would not have seen if the illusion wasn't directly linked to his emotions. So there are some emotions there we have yet to see, though I don't believe it is that he wishes to hide them.

As I said before, Hibari isn't incredibly complex. The image above is a part of the Inheritance Ceremony Arc in which Hibari fights Adel for their "pride." When she asks him what he feels the most pride in, he mentions that he doesn't quite understand the feeling of pride. I think what little we see of Hibari's emotions is not because he is trying to hide them, but moreso that he doesn't quite understand what he's feeling and therefore has no real way to express it. I also believe that Hibari hasn't revealed anything about himself, his past or anything of the sort not because he wants to keep it a secret, but because it has not been relevant to do so. And the more time he spends talking, the less time he spends fighting... and well, e already know his priority ^.^;