Motoyasu Kitamura/Relationships

Naofumi Iwatani
To say that Motoyasu and Naofumi had a hostile relationship is a severe understatement. In one of the first conversations, the two of them had together Motoyasu openly calls Naofumi useless due to his shield. When Malty made her accusation the person she went to was Motoyasu who immediately believed her lies and causing his opinion of Naofumi to severely worsen.

Every time the two of them interact with one another it typically follows the pattern of yelling at Naofumi for whatever 'crime' he's committed on that occasion, trade insults, gets Filo to kick Motoyasu away. Naofumi's hatred of the spear hero goes so far that he's given Filo the standing order to kick him away every time she sees him.

Following his awakening to the Lust Series Motoyasu pulls a 180 degree turn on Naofumi: having fallen in love with Filo Motoyasu views Naofumi as the one who raised her as his future Father in law, therefore anything he says Motoyasu takes as gospel to the point that he will do anything Naofumi tells him to do even if he dislikes it or disagrees with it.

Naofumi for his part sees the broken Motoyasu as at best a useful idiot and at worst an annoyance to be pushed off someone else or tricked into going as far away as possible.

Raphtalia
Motoyasu was under the impression that Naofumi was forcing Raphtalia to be his sex slave and tried to save her in an unfair duel with Naofumi, but was shocked when Raphtalia slapped him for his actions. He argued that no one should be forced to fight, but still, she chooses to follow Naofumi. The other heroes called out on him for his unjustified duel.

He again tried to defend himself by claiming that Raphtalia must have been brainwashed, to which no one agreed. When Naofumi was accused of having the brainwashing shield, having received evidence to back up his delusional claims he fought with renewed vigor to try to free her and another female companion of Naofumi's supposed brainwashing.

After Naofumi's name was cleared, he no longer sought to free Raphtalia from Naofumi and acknowledged Raphtalia's genuine feelings for Naofumi, as he questioned Naofumi on his progress with Raphtalia in the bathhouse of Cal Mira Island, only to be angered by Naofumi's obliviousness to her feelings. After his curse series activated, he could only see Raphtalia as a pig, referring her as a Tanuki Pig

Aultcray Melromarc XXXII
Due to being the hero whose party his daughter was a part of, Motoyasu received a lot of favorable treatment from the king, it is mentioned that the King personally gave Motoyasu requests to complete and when the time comes to hand out payment to the four heroes Motoyasu received slightly more than Itsuki and Ren. Additionally, it also seems that Aultcray stockpiled rare materials for Motoyasu to use in his weapon reinforcement method.

Post Curse Series Motoyasu is a different story, he despises the King for his treatment of Naofumi and refers to him only by the name Naofumi gave to him: Trash.

Malty Melromarc
Motoyasu always defended and believed Malty. Malty also got jealous of any girl who got close to Motoyasu, she even kicked a few members out of his party without his knowledge. The only thing she liked about Motoyasu was his looks. He believed every word coming from her mouth without any doubt. Motoyasu never noticed any of her suspicious behavior. He was the only one who refused to believe Malty to be a criminal, even after all the evidence was presented and she had been questioned about her crimes while under the influence of a slave seal that forced her to tell the truth and continued to believe in her.

It was revealed that both of them had a physical relationship which Motoyasu believes to be her first time. But Malty and her friend just used to seduce him for their own personal gains. After the spirit tortoise incident, she completely abandoned him. Despite which he searched his comrades, only to be shocked by the real personalities of Malty and the others.

The current Motoyasu's opinion of Malty can best be summarized by his name for her: The Red Swine, and even refers to her as such in his memories of her prior to his insanity.

Elena Haven
Unlike the other party members, She genuinely liked Motoyasu. She was not bothered by his interest in other women and considered it normal for men to have pleasure. She went along with Malty to secure her place in his party. But she couldn't digest his rash and irrational behaviors. She also didn't like how he used her and other women as a status symbol. Finally, she had had enough of being in his party and abandoned him, after seeing that he was unable to do anything against the spirit tortoise. To save herself from crown's capital punishment, she sold out Motoyasu and told all of his flaws to his face much to the latter's dismay.

Rino
Motoyasu wooed her to try to get her to join his party. But when she joined Rino was taken aback by his party's fighting style where the women cheered while Motoyasu was fighting and showing off. Malty and some other female companions of Motoyasu took her and sold her as a slave, and they told him that she left the party, as she couldn't keep up with them. Motoyasu once crossed paths with her after she became a slave but was deaf to her cry for help, refusing to believe that she was even there. Her fate after this is unknown, except for the fact that she is suffering.

Filo
Filo hated Motoyasu from the moment he met her, mostly for the Fat bird insult, and immediately sent him flying through the air. Naofumi has given her the standing order to send Motoyasu flying with a kick every time they meet. When Motoyasu saw her human form for the first time he immediately developed a crush on her, on account of his fetish for angels, unfortunately for him, he insulted her monster form for a second time and was rewarded with a second kick sending him flying.

After being betrayed by his comrades, Motoyasu was completely broken. Seeing his broken spirit, Filo tried to cheer him up and ended up as his goal of affection, much to her dismay. He caused Filo, a new trauma of not letting go. Naofumi used Filo to manipulate Motoyasu to fight the waves with him.