As one of the executives of the Port Mafia organization, Chuuya is considered to be one of the best-dressed amongst other members. Chuuya wears a slim-cut white shirt with a grey vest, not to mention his signature black hat as well as a black coat that he wears covering his body. Hindsight, his appearance does resemble of the traditional Italian mafia clothing, with black as the main color.

Chuuya appeared to have quite the liking on hats, as he is seen to always wear one wherever he goes. Due to his unique sense of style, Dazai is seen making fun of him. Also thanks to his liking of hats, Chuuya is also known to be called, Mr. Fancy Hats.

Now, although Chuuya can be very smart as he is very much capable of assessing the current situation before taking any necessary actions, he is quite the gullible guy, as it was shown during the series where Dazai often plays tricks on him, or even pranks him. Funny thing is, he kept falling for it. This is one of the things that makes Chuuya Nakahara such a unique character, as he can be intimidating yet funny at the same time.

As seen in episode 21, when he and Dazai meet again on a mission to save Q, Dazai appeared to have his right arm bandaged and put in a sling as if he was injured. After getting attacked by Lovecraft, one of the members of The Guild, Dazai pulled a fast one on Chuuya, as he pretended to lose his whole arm and surprised Chuuya with his arm still attached. Nevertheless, it’s fun to watch them both.

Just like what was mentioned in the preview paragraph, Chuuya Nakahara’s partnership with Dazai Osamu is definitely one of the most intriguing things about this character. Although it hasn’t been shown in the series, but it has been revealed by Mori Ougai, the leader of Port Mafia that their partnership and alliance was called the most devastating rivalry in history. Their former alliance was called, “Double Black.”

Having that kind of partnership, it comes as second nature that both of them know each other very well, including each other's moves and attack patterns. This was revealed in episode 21 where Dazai was able to easily dodge Chuuya’s attack.

Although it is unclear how both Chuuya and Dazai come to hate each other, their hate was very apparent as seen in episode 21, where Dazai claimed to be the one responsible for setting up a bomb under Chuuya’s car the night he left the organization. Their hate probably stems from their rivalry and maybe because Dazai went out and left Port Mafia.

Being in rank with one of the top echelons of the Port Mafia, Chuuya Nakahara possesses a really scary and powerful gifted ability. His ability, called ‘For The Tainted Sorrow’, allows him to manipulate gravity, even the gravitation of himself and of those that he touches. This ability is very unique in terms of how he uses it, in episode 21, you can see that Chuuya was able to use his ability to float in the air.

One other thing about Chuuya’s abilities is that he has a ‘Corrupted Form’, the next-level of his ability that allows him to manipulate the gravitation around him. It increases his density that allows him to be able to devour incoming attacks and even shoot out little black holes that disintegrate anything. The downside towards this dangerous ability is that he has no control over it whatsoever, as he will continue to devour anything and everything until he dies.

This ability was shown in episode 21, where Chuuya used it to defeat Lovecraft, a member of The Guild. It was up to Dazai, who has the ability "No Longer Human", which allows him to nullify others' abilities, to cancel out the rampaging Chuuya in his Corrupted Form, showing how well they both work together. Chuuya uses the verse:
“Oh, Grantors of Dark Disgrace, Do Not Wake Me Again” to activate the Corrupted Form.

As you probably already know, Chuuya is considered to have a pretty short fuse. This can be seen throughout the series as he seemed to always fall for Dazai’s little tricks and provocation. Chuuya likes to taunt others into fighting him and seems inclined to do it. But nonetheless, he can be very analytical when it comes to certain situations, assessing every nook and cranny of the things at hand, their considered to be smart and wistful.

One such incident can be seen in episode 18, where Chuuya was able to infiltrate the Armed Detective Agency’s secret hideout alone to reveal that Port Mafia has set up a trap for The Guild by leaking the addresses of the Detective Agency's clerks.