Jonathan Joestar/Personality and Relationships

Personality
"He's not just looks and clothes, but a real honest-to-god gentleman... I like it!"

- Speedwagon

During his childhood, Jonathan was rather proud and mischievous. Despite already aspiring to be a "true gentleman", Jonathan lacked manners and mostly behaved like a normal child, despite his lonely youth. Still, his unwavering determination was already visible, as he stood up to Dio's harassment.

First and foremost, Jonathan strives to become a "true gentleman." He carries his Joestar name with pride, never betraying the code of conduct he has set for himself and will treat any fellow human with respect unless they prove evil.

Jonathan also possesses a fierce inner strength and the drive to face and overcome conflict, which Dio calls an "explosive power". That drive, fueled by his affection to his friends and loved ones, enabled him to overcome the direst situations, notably managing to save his wife Erina when their boat was overcome with zombies and he was fatally hit in the throat. Jonathan fights for what he believes in, and once he is committed to something, he won't back down until the deed is done. During his journey to find a cure for his father's illness, he was ambushed by a band of misfit hoodlums. He did not so much as flinch as he grasped an assailant's knife within his hand, saying he had much more riding on the fight than merely four fingers.

Kind, positive, and sometimes naive, Jonathan has a mindset where he tries to imagine the consequences his actions would have on other people, even if they appear to be enemies. He is gentle and sympathetic, feeling pain even as he vanquishes a zombified copper. Despite his skill in fighting, he will never seriously harm a person without a valid reason. In the end, even after everything Dio has done, Jonathan still considers him his brother, and sheds tears for him. His courteous nature as well as his mental fortitude and ability to withstand fear and pain, is the main reason Speedwagon decides to aid him on his journey.

Yet Jonathan can feel righteous fury at the evilness of his foes, and will conduct justice by vanquishing them. He admitted that his reason for fighting Dio wasn't out of duty for saving the world, but to avenge his loved ones Dio killed.

With his courage and spirit, Jonathan sets a legacy as the first JoJo of the series.

Family

 * George Joestar I: In his youth, Jonathan's father was very strict on him, correcting his lack of table manners and berating his studies, while ignoring the harm that Dio was bringing on his son. This was perhaps made worse by the fact that Jonathan's mother had died some years ago, hardening George and causing him to be harsher on his son. Regardless, Jonathan still loves his father greatly, angrily beating up Dio, whom he had been friends with for the past seven years, for poisoning his father. When Dio throws a knife at Jonathan, George sacrifices himself to block the knife and comments that "it's not so bad to die in your son's arms".
 * Mary Joestar: Though Jonathan's interactions with his mother are never seen as she is killed while he is still an infant, he is shown to love her greatly, looking at her picture wistfully and crying right after Dio ruins his life with his arrival.
 * Danny Joestar: Jonathan and Danny have forged a strong bond since Danny saved Jonathan from drowning in the river. Jonathan is shown to be very angry when Danny was kicked by Dio and had sobbed uncontrollably when the household had buried Danny. Danny still shows up in his master's memories, when Jonathan remembers having fought with Danny over a bone.
 * Dio Brando: In their childhood, Dio and Jonathan do not get along well due to Dio's antagonism towards Jonathan and his ability to both outshine him and ruin his relationships greatly. Years later at Hugh Hudson Academy, Jonathan is shown to have become friendly with Dio, though Jonathan still suspects that something is suspicious about Dio's behavior and Dio had been plotting to take over the Joestar household. Their antagonism reaches a peak when Dio poisons, and later kills, Jonathan's father and transforms into a vampire. Regardless, both maintain some degree of respect towards one another, as shown when Jonathan suicidally attempts to pin Dio on a pointed statue as the Joestar mansion burned down and Dio acknowledges Jonathan shortly before attempting to take over Jonathan's body. Their relationship sparks a legacy that continues well into the future parts of the series.
 * Erina Pendleton: Jonathan's love interest and eventually his wife first hands him a handkerchief shortly after he is beaten down by bullies. Jonathan professes his love for her afterwards, which she is shown to accept at least in part, until Dio enters and steals her first kiss in order to upset the two. Erina does return after the Joestar mansion burns down, however, and nurses Jonathan back to health, igniting the relationship between the two once more. The two are married after Jonathan manages to defeat Dio with his ripple, and their relationship continues well into Erina's old age, where her memories of Jonathan prevent her from entering a relationship with Robert Speedwagon.
 * Giorno Giovanna: Many years after Jonathan's death, Dio uses Jonathan's body to get around in the world now, during which he sires 4 children, one of which is Giorno. Of all the children, Giorno is born first and carries the birthmark thanks to Jonathan's DNA presence in his body. While a slightly darker side of Giorno exists resembling Dio's ruthlessness (albeit toward evil people), he retains a noble heart and desire to help innocents closer to Jonathan's ideals.

Friends

 * Robert E. O. Speedwagon: Jonathan's most loyal friend. An enemy at first, he later joined Jonathan on his quest after seeing the protagonist's dedication and courteous nature. In his later years, he founded The Speedwagon Foundation, which has become the Joestar Family's most useful asset in battling Stand users and supernatural research.
 * William Anthonio Zeppeli: Jonathan, upon meeting Zeppeli, was initially perplexed by his appearance and strange abilities. After Zeppeli explains his actions and the significance of the Ripple, Jonathan grows to trust Zeppeli completely and looks up to him as a mentor. Zeppeli eventually sacrifices himself to save Jonathan and transfers his energy and life force to him, moments before dying. Jonathan tearfully avenges Zeppeli by killing Tarkus.JonathanFriends.png
 * Poco: As with the rest of his party, Jonathan felt it necessary to look after Poco during his battle against Dio and his undead army. He takes it upon himself to save Poco's sister during their infiltration of Dio's castle.
 * Tonpetty: Given the short time-sharing, their relationship was nothing more than a cordial respect and empathy with them over the death of Zeppeli.
 * Dire: Dire died too fast to exchange more than a few words with him. However, it is Jonathan who takes revenge on his hands against Dio.
 * Straizo: Given the short time-sharing, their relationship was nothing more than a cordial respect and empathy with them over the death of Zeppeli. However after Jonathan's death, it is Straizo who adopts the child that Jonathan's saves and gives to Erina and eventually teaches the child in the ways of the Ripple. Since Straizo's adoptive daughter married his son that would essentially make them brothers-in-law.

Enemies

 * Dio Brando: In their childhood, Dio and Jonathan do not get along well due to Dio's antagonism towards Jonathan and his ability to both outshine him and ruin his relationships greatly. Years later at Hugh Hudson Academy, Jonathan is shown to have become friendly with Dio, though Jonathan still suspects that something is suspicious about Dio's behavior and Dio had been plotting to take over the Joestar household. Their antagonism reaches a peak when Dio poisons, and later kills, Jonathan's father and transforms into a vampire. Regardless, both maintain some degree of respect towards one another, as shown when Jonathan suicidally attempts to pin Dio on a pointed statue as the Joestar mansion burned down and Dio acknowledges Jonathan shortly before attempting to take over Jonathan's body. Their relationship sparks a legacy that continues well into the future parts of the series. In the end Jonathan failed to stop Dio and his body is possessed by him.
 * Wang Chan: As the man who gave Dio the poison that was used to try and kill his father, Jonathan despised Wang Chan. Unlike Dio, Wang Chan had no respect for Jonathan and constantly insulted him. During his final battle with Dio, Jonathan used the last of his Ripple to kill Wang Chan and use his body to blow up the ship and Dio with it.
 * Tarkus: Jonathan was originally awestruck at Tarkus having learned of him in history books, but after he destroyed the remains of his comrade Bruford, Joathan lost all respect for him. The two would later battle in a castle chained together and said battle would lead to Zeppili's death, in anger and sadness Jonathan destroyed Tarkus.
 * Bruford: Like Tarkus, Jonathan highly respected Bruford do to his reputation as a great fighter and knight. After their battle, Bruford also grew to respect Jonathan and gave him his sword before his death.
 * Jack the Ripper: Because he was one of Dio's minions and an infamous serial killer, Jonathan knew Jack was a threat and had to be stopped. In the end, Jonathan destroyed Jack with his Ripple.

Relationships in Eyes of Heaven
(The information below derives from a Video Game not written by Araki. As such, it may not be considered canon.)