But it seemed that fate had other intentions for the twins.
On the day of her tenth birthday, her father, Zeoticus, announced the advancement of the alliance between the prestigious Gremory Clan and the powerful Phenex Clan, through an arranged marriage between Rias and the third son of the Phenex Clan, Riser Phenex.
Despite being given little autonomy in the matter and forced into a union she did not want, Rias refused to accept her father's proposal.
However, Zeoticus was determined to go through with the marriage, insisting that it was vital to the continued prosperity and success of the Gremory Clan. It seemed that Rias was facing an arduous and uncertain future, with very little control over her own destiny.
While dealing with this arduous and uncertain future, Rias turned her gaze to her twin brother, Shoto, expecting to see him grinning at her unfortunate situation.
However, to her astonishment, she discovered him standing there with a solemn expression on his face, and his features contorted into a slight scowl of anger.
It was the first time in many years that Rias had seen Shoto display any emotion other than his typical cold and aloof demeanor, and she could sense a feeling of camaraderie and understanding in his gaze.
As they locked eyes and exchanged a nod of silent agreement, Rias understood that they were both united in their belief: this marriage could not be allowed to take place.
Shoto genuinely empathized with his twin sister, who was caught up in such a cruel and unfair marriage arrangement, being fully aware of her dissatisfaction and reluctance towards him.
But more importantly, Shoto also had great disdain for Riser's deplorable personality. From what he had observed and heard, Riser was an arrogant, rude, and selfish playboy with a pretentious attitude, something neither of the Gremory twins could stand or accept.
He was determined to do something to safeguard his sister from being forced into such an unhappy and loveless marriage, and he was determined to find a way to prevent it from happening.
While the twins were in the midst of devising a way to prevent Rias' forced marriage to Riser, the latter decided to make an immediate attempt to win Rias over by using his so-called "charms" to persuade and flatter her.
However, in the process of trying to ingratiate himself with her, Riser made the grave mistake of treating Rias poorly by treating her as a mere object instead of a person. At Rias' resistance to his advances, Riser punched her in the face, causing her to tip over and fall.
This was a profound change in demeanor for Shoto, who was known for his calm and collected personality, as he witnessed Riser mistreating his twin sister. His demeanor drastically changed as he was overcome by a great rage and anger that he had never shown before.
Hurting Rias was to Shoto what committing a sin was to an Angel, an unforgivable crime that deserved death. However, even in the midst of his simmering anger, Shoto knew that he couldn't afford to kill Riser Phenex in front of Lord and Lady Phenex, considering the repercussions it would have on his own family.
But at that very moment, his rational mind was darkened by his ferocious fury, as a crimson aura began to envelop his body. On the rare occasions that Shoto spoke, his voice was suffused with venomous hatred, conveying his contempt and disgust for Riser's actions.
It was clear that Shoto would not rest until justice was done for his twin sister, and he would spare no effort to protect her.
"I... am not one... to be controlled by sheer emotion..." Shoto said with a low growl, surprising Rias at the new tone he was using. "But... if anyone... dares to harm my family..." he snarled with a new intensity in his eyes that startled everyone around him, his voice imbued with a dangerous and deadly undertone.
"THEY'RE GOING... TO PAY!" Shoto's voice reverberated throughout the throne room, as a fiery crimson aura erupted from his body, lighting up the room with its intensity.
The power that emanated from him was palpable, and it was unmistakable that he meant every word he said. No one would dare hurt his family, not while he still possessed the power to defend them.
From then on, Shoto's anger never seemed to dissipate as the flames engulfing his body grew to an enormous size, nearly engulfing the entire room with a fiery inferno that glowed a brilliant red hue and intensity.
Rias watched in amazement as her brother's anger was translated into his flames, a display of power that left the onlookers in awe. Riser made the mistake of looking into Shoto's eyes, as if he was looking into the eyes of a true demon in its infinite rage.
The sheer intensity and ferocity in his gaze was enough for Riser to immediately take a step back, fear etched on his face. Shoto was clearly not to be trifled with, and his anger was not to be underestimated.
With the power and intensity of his flames increasing with each passing moment, Shoto continued to advance towards Riser, his gaze firmly fixed on his intended victim.
Riser, realizing the mortal danger he was in, hastily backed away, tripping over his own feet in his panic to escape, but it was evident that he had no way to do so.
The inferno surrounding Shoto was so intense that it was as if the very air around him was igniting. Thanks to his Phenex heritage, Riser had been gifted with immortality, affinity for fire magic, and resistance to said magic that would keep him alive... if he's lucky.
But as Shoto's anger continued to rise, it seemed his fate was uncertain, with Riser's destiny hanging precariously by a thread.
The members of the Gremory and Phenex clans present in the throne room were horrified by the unfolding events, some of them desperately trying to put out the raging inferno, others trying to intervene and stop Shoto's advance.
However, with Shoto's flames fueled by the Power of Destruction, it was apparent that he was gripped by an all-consuming rage, his anger clouding his judgment and rendering him unresponsive to reason or moderation.
Riser, now lying on the ground in a fetal position, desperately trying to shield himself from the searing heat and the relentless onslaught of the flames, filled the air with his screams of terror and agony.
The bystanders were witnessing the sheer terror etched on Riser's face, and it was clear that he would not survive the match unless some sort of intervention occurred. It was a truly terrifying and tragic scene, one that would leave a lasting impact on all who witnessed it.
Rias, who had initially been consumed by a sense of euphoric satisfaction at seeing her brother Shoto unleash his blazing wrath on Riser, the object of her scorn, was quickly overwhelmed by a sense of horror as the ramifications of the scene before her fully unveiled themselves.
Without hesitation, he ran in a panic, his mind consumed by a single goal: to reach his brother and end the destructive conflagration. As she ran, Rias's heart was beating wildly inside her chest, her mind clouded by a mixture of fear and despair.
Despite her hatred for Riser, she knew deep down that he did not deserve to be brutally cremated like this, and her conscience would not allow her to stand idly by while the bonds of the Gremory Clan and the Phenex Clan were jeopardized.
Reaching Shoto, Rias hugged him from behind, pulling him with all her might as she pleaded with a trembling voice for him to stop his deadly attack.
Her words, however, fell on deaf ears, as Shoto's flames licked at her flesh, making her scream in pain. But through the agony, Rias endured, her determination to save others stronger than her own suffering.
As the flames continued to ravage Rias's body, Shoto finally began to realize the true extent of the damage he had caused, and the sight of his sister's suffering abruptly dissipated his anger, causing the flames to fade and turn into smoldering embers.
As the smoke and ash cleared, and the full extent of the devastation he had caused lay bare before him, Shoto's eyes widened in horror at the extent of his Rias's injuries.
Her once flawless skin was now marred by blistered flesh and charred red skin, covered in burn marks. Her body was wracked with the kind of agony only major burns can inflict, a direct result of Shoto's own unbridled rage.
The sight of blood running down Rias' face sent shivers of panic through Shoto's body, his heart pounding in his chest as the gravity of what he had done hit him like a freight train.
Rias lay limp in his arms, her breathing shallow, her eyes closed, and her body completely vulnerable. He could feel the warmth of her blood seeping through his clothes, and he knew she was in terrible condition.
The Gremory price, who had always been so emotionless, was now consumed by feelings of regret, self-loathing, and guilt as he realized that he had inflicted immense pain on a person he'd tried to protect.
The scene that unfolded before him was truly heartbreaking, with a grim atmosphere that left everyone who witnessed it feeling devastated. Seeing his sister in such terrible conditions was unbearable, and he knew that he was responsible.
"No... no, no, no! Rias! I'm so sorry!" Shoto cried out in pain and grief, his voice shaking with fear and horror at what he had just done.
He cradled Rias's body in his arms, tears streaming down his face as he looked down at his sister in desperation.
"Please, I didn't mean to! Wake up!" Shoto begged over and over as he waited for his sister to awaken from her unconscious state, and his heart filled with nothing but deep regret.
Seeing his sister injured and unconscious was more than he could bear, and he let out a heartbreaking sob as he held her tight, begging her to wake up and forgive him for his mistake.
It wasn't until hours later that Rias woke up from her near-death experience, her mind completely blank from the trauma she had endured.
Thanks to the most skilled healers' healing magic that Zeoticus was able to provide, Rias was able to quickly recover with minimal scarring from her burns. It was discovered that flames powered by destruction magic left more lasting scars even healing magic couldn't mend.
Shoto's crying face was the first thing she saw when she opened her eyes after waking up. She noticed that Shoto also had a large burn scar on the left side of his face, extending from his hairline to the middle of his cheek. Said scar being an accidentally self-inflicted one, for Shoto's flames had become too much for even he to handle.
"Rias, I... I'm so sorry..." Shoto started to say, his eyes brimming with tears as he held his sister tightly in his arms. "I'm so sorry... I'm sorry...! I hurt you more than that Phenex bastard hurt you...!"
Shoto was completely broken at this point, tears freely flowing from his eyes as he looked at Rias. "I'm... so... sorry... " he repeated over and over again.
Rias looked at Shoto in shock and disbelief at what she saw. After a few seconds of silence and contemplating her situation, Rias began to tear up as well.
"Shoto..." Rias said quietly through her tears, before hugging her brother. "I forgive you... Shoto... you tried to protect me despite everything... All these years, I thought you'd never care about me... I thought you'd never consider me important..." Rias whispered as she hugged Shoto tightly.
"You were always so cold...so different...I thought you isolated yourself from me because you didn't care..." Rias continued to whisper as she wiped her brother's tears from her cheeks.
"But...I was wrong...you did care...you were the only one who jumped on Riser the moment he hurt me..." Rias said as she looked at her brother with tears in her own eyes.
"I don't care if the result wasn't the most... harmless, to say the least... I love you... Shoto..." Rias said with a shaky voice. "I love you so much...brother..." She repeated once more, leaning in and hugging her twin as tightly as her aching arms would allow.
Shoto smiled slightly, tears filling his eyes as he hugged his sister back. "I love you too, sister..." He said for the first time as he held her close to him.
From the bedroom door, Venelana watched her children with a soft smile on her face. She was happy to see her children repair and strengthen their bond at last.
Rias was happy to finally receive the attention from Shoto that she had always wanted, feeling a warmth fill her heart. No, it wasn't about attention anymore... It was about their bonds as brother and sister, as twins, as family.
Unfortunately, to interrupt this touching moment, Zeoticus entered the room, a serious expression on his face as he looked at Shoto. He scolded the twin for being so reckless in trying to attack one of the sons of the Phenex family.
"Shoto, while I appreciate your concern for your sister's well-being and safety. But I can't let you risk our bond with the Phenex Clan. The wedding between Rias and Riser is scheduled for a time when they are both of legal age to wed. Regardless, whether you like it or not, this wedding is necessary." Zeoticus said as he left the room.
Shoto's face darkened upon hearing Zeoticus' words. "Well, until then..." He said, stopping his father with his words. "I will fight. I will fight to become stronger than Riser. I will fight for my sister's happiness..."
Shoto spoke with determination in his eyes. "I will fight... for her freedom. Mark my words well..."
"Father..."
Rias could feel the particular tone in which Shoto accentuated the word "father" in his speech. It was undoubtedly mixed with a poisonous undercurrent.
Shoto's voice was filled with hate and bitterness as he finished speaking, before Zeoticus dismissed him with a wave of his hand. In a few years, he would see if Shoto's words were empty bravado or if they would come true.