Kirishima Miyama

Kirishima Miyama is Yoshino's fiance and the grand nephew of the head of Miyama Yakuza group. He is described as handsome but concerning.

Appearance
Kirishima has spiked short black hair with green highlights. He has a lean muscular body type and yellow eyes. He is not very tall compared to Yoshino, as he was shorter than her when they were 13. He has dragon and tiger tattoos which he often hides when he is wearing a sleeved shirt. Most people he comes in contact with mention that he is very attractive.

Personality
Kirishima has been described as a masochistic psychopath by most of his yakuza peers and Yoshino. His parents were mentioned to be scared of him, which led him to living with his great uncle, Gaku.

Although Kirishima is known to be very cordial at school with a pleasant face, he can become extremely violent when upset. Yoshino has seen this on multiple occasions when she has been harassed or injured by men. Despite his politeness towards the general public, he thinks little of other people's feelings, particularly how his actions affect those around him. This has led Yoshino to say that she doesn't understand him or the way that he thinks or feels, and generally feels that he's basically inhumane. He is also a part of the upstanding citizens club in his high school--something that annoys and confuses Yoshino.

Kirishima is shown throughout the manga to be incredibly strong, as he can almost kill a whole group of men with his bare fists. He is also very blunt when it comes to admitting his feelings, telling girls off instantly when he thinks they are too stereotypical or telling Yoshino that he wants to marry her despite the short time they have known one another. Kirishima is also one who can predict everything, since he is always thinking.

He is also shown to be extremely sexually active, losing his virginity at 12 and having several playmates at a time, despite his betrothal to Yoshino. At the moment, he's 16 years of age as mentioned when Yoshino was first introduced to him by her grandfather. Her grandfather mentioned that Kirishima is "around your age".

Kirishima enjoys pain, something that his yakuza peers are even thoroughly confused and disturbed by. Examples of his weird antics include getting knee surgery without anesthesia (his request), suffocating yakuza captives (because he thinks they'd like it), purposely not making curfew to get punished, and telling Yoshino to "fuck him up". He also enjoys when Yoshino is angrily lecturing him.

Somei Yoshino
Yoshino is Kirishima's arranged fiance and the granddaughter of a well known Yakuza. Kirishima and Yoshino are initially only tied together by their family's idea of an arranged marriage. After becoming tired of Yoshino's "tame" personality he even goes as far to tell her that she would be worth more to him as a prostitute. Yoshino then sells her kidney on the black market and pays Kirishima even more money than what she would receive selling sex. After this encounter, Kirishima becomes obsessed with Yoshino, going as far as injuring others and stalking her. Yoshino seems to be the only woman that he also genuinely cares about, although his actions towards her can sometimes be confusing. He is shown to become extremely jealous of her relationship with her childhood friend, Shouma, even though he himself sleeps with other women consistently. Admittedly, Yoshino also appears to be the first legitimate friend (female friend in particular) that Kirishima has ever had, therefore, he even likes doing mundane tasks with her.

It is shown that Yoshino eventually learns his behavior over the series despite his complicated personality, and later takes advantage of them.

His side chicks
Due to Kirishima being a playboy, he has numerous casual side chicks that he engages in sexual activity with (Nao and Ayano being the only ones named). He generally has no romantic feelings for any of them, but they all work out to be his 'friends'. He regularly mentions his feeling for Yoshino to them, even after intercourse, to where they tell him that he is a garbage human being, and Yoshino should just dump him. They also give him information about girls and news, which is how he gets to acknowledge anything.

Miyama Gaku
Even though Gaku is his adopted grandfather he is technically his great uncle. Gaku and Kirishima don't interact much in the story, although it is shown that Kirishima has been under his care since he was little. It is mentioned a few times of Gaku's regiment punishment towards Kirishima when he would break the rules. After looking at old photos, Yoshino even mentions that Kirishima greatly physically resembles younger Gaku (before he had his scar). Gaku is later revealed that he usually gives Kirishima an amount of money monthly to survive therefore not really taking care of him, and Kirishima has to learn his own way of being independent.

Kirishima often showed signs that highly resembled Gaku's manner, like having the same laugh, both are good in fighting, both cannot drink sake and many people thought Kirishima is just Gaku but younger, especially if Kirishima gelled his hair backwards.

Somei Renji
Renji and Kirishima have an interesting dynamic that is unfolding within the manga. Initially Renji was just in favor of his granddaughter Yoshino marrying Kirishima. However, Kirishima seems to keep in contact with Renji giving him updates on Yoshino's well being (unbeknownst to her), and Renji wants Kirishima to behave in a stalker-ish attitude while caring for her.

Tachibana Aoi
Tachibana is Kirishima's collegue. He appears to be similar in age to Hotei. Tachibana usually enforces the curfew rule and will strike Kirishima when he breaks it. Tachibana also doesn't understand Kirishima's love for Yoshino, only seeing her as an arrogant, selfish, spoiled brat. Tachibana also does not tolerate Kirishima's masochistic behavior and stated that he is annoyed or disturbed by it.

Toriashi Shouma
Shouma and Kirishima seems to dislike each other since they both care about Yoshino in similar ways. Shouma thinks that Kirishima is a psychopath and Kirishima sees Shouma as a 'swine'. In a side story, Kirishima also admits that he is jealous of Yoshino and Shouma's relationship. Kirishima will not ever kill or attack Shouma despite disliking him, due to him being part of her family. Over the course of the series their hatred for each other only continues to grow, as Shouma gets more irritated by him constantly annoying if not negotiating him for a reply. Eventually a deadly fight happened due to Kirishima negotiated Shouma by using his dating status with Yoshino as a way to trigger him. Kirishima also would get internally frustrated or angered if any kind of attention from Yoshino were to be given to Shouma.

Akashigata Tsubaki
Kirishima has zero to no reluctance to tell Tsubaki about how Yoshino is to him. They tried to get along, only for Tsubaki to despise him in reality. Kirishima asked her about Yoshino's kidney, to find out that Yoshino technically lied about it and gave away 1500 milimetres of her own blood for money instead, for this Tsubaki has since looked down on Kirishima. She also thinks of Kirishima as childish and immature and generally does not like him at all. Tsubaki despises him, and thinks of him to be somewhat predictable, as she calls his mind is easy to read. She also knew that Kirishima purposely fought Shouma in order to hide the fact that Renji has previously beaten him up, and to make Shouma the bigger culprit.

Nao Shiota
Nao is a model and Kirishima's summer-fling. They went to the same middle school. They've "dated" while Nao came to Japan during her summer vacation (chapter 13). In chapter 16.1 Kirishima stated that he never had a girlfriend and rather that all the girls he were "dating" were patrons. In chapter 16.2 Kishirima revealed that he only went out with her to expand his network of contacts and she only approached him because he is a yakuza, a contact she could use to threaten others.

Kento Ozu
Kirishima and Ozu possibly has a vague connection with each other, other than Nao Shiota was their ex-girlfriend. Kirishima also revealed to Yoshino that Ozu barely knows her other than her name. According to him, Ozu has harassed Kirishima for information before.

Azami
It is possible that Azami travelled from Tokyo to Osaka just to find Kirishima. Azami uses Ozu to harass him, as Kirishima stated without mentioning the latter's name, rather he calls him as "Ozu's superior".

Trivia

 * It is shown that Kirishima has advanced technology, and can clone Yoshino's phone.
 * Kirishima is shown to not really sleep much, as he stated that he is more active when everyone is asleep, yet somehow, he is always active even during the morning.
 * He has really fast speed, as he can run 1 kilometre for only 3 minutes. Yoshino describes this of him as inhumane.
 * He is likely the youngest character in the manga, as he stated he will turn 18 at his next birthday, revealing that he's technically 17 and underage to do anything taboo that he has done.
 * Kirishima takes advance math classes, but doesn't really study much but memorized them, this is to prove how intelligent he actually is.