Far above the Earth where the divine spend their lifetime maintaining peace within their world and beyond, Aether was born in the realm of gods and greater beings. Although, this sacrificed his human mother to which he didn't have the ability to live long enough with Aether's father: Charlemagne, the God of all Harmony and Music. His life-span would last forever, in comparison to his mother - only lasting for barely three decades before she died from giving birth to this demi-god. Devastated, Charlemagne continued to raise his boy as carefully as he could but he had mixed emotions towards him when his wife passed. He had more important responsibilities to keep up at the same time looking over his child single-handedly with little or no support from his advisers.  Eventually the God grew fond of his child the more he grew, eventually he'd compare his beauty like his mother - he began to adore him and acted like a doting father. Charlemagne selfishly ignored anyone who tried to volunteer in caring for young Aether and continued to raise him himself - only sometimes disregarding his work of a God. Although human, Aether and his father finds out that the young boy had a voice like no other; a soothing and soft tone to ease away all the stress Charlemagne can withhold. Charlemagne only realizes it until Aether was in his teen phase and now teaches him to become an adept spellsinger. Eventually Aether grows into a fine, beautiful man which Charlemagne still continues to dote on him like on any other day. Although Aether doesn't seem to act like a spoiled son the whole time he was growing - he always watch his father work his way between his son and his responsibilities.

Aether became an expert and eventually almost a master in spellsinging - one of the abilities that his home land grasped onto for such a long time. Let alone, one of the more important abilities that Charlemagne must rely on for his song to work. However, as Aether was half-human his abilities were still limited and prevented him to be able to progress. But he still remained to be better than most spellsingers. Even at adult age and as an experienced spellsinger, Charlemagne continues to lay his attention onto his only son - which brings inner-world problems. Eventually envy is brought throughout the God's advisors and those who surround Aether would grow jealous of his existence. One of Charlemagne's more caring servant and spellsinger eventually brought up the idea of ridding of Aether's existence out of jealousy.

Aether was lead to a trap, he almost costed his life before his voice saved him and Charlemagne appeared... with more anger rising up once Aether had lost his vision on one eye. After he healed his wounds, giving him a pair of horns and a mask to cover it, Aether's father becomes insecure regarding Aether's safety in their homeland. Under his father's commands he was confined to their home for the sake of Aether's safety and he lacked the freedom of being able to roam around the Ophiuchus region without the company of his father. The young man becomes more mindful, feeling as if his existence did burden his father - he makes the final desicion to flee the region and descend down onto Earth's clouds and experience the world his late mother had once lived in before his father brought her home.

The spellsinger acts as one of Earth's smaller guardians and helps those that he thinks is best for Earth. His spellsinging abilities is limited to how well Earth can change from it, but he continues to help contribute with humans that he favors from time to time.

Cathal's golden age

Aether spent years traveling among Earth's lands, but eventually was drawn to the Circle Kingdom known as Cathal. And just outside the vicnity, a few miles from the walls, he stumbles upon a struggling young woman fighting for her life. Aether, who is attached to these mortals, never hesitated to aid her as soon as he saw her troubles. Elabelle owes him her life since then and welcomes Aether into Cathal with open arms.

As to why Rhythmonius was drawn to Cathal, he is currently remaining in the Circle Kingdom until he discovers the origins of this prosperous city. He spends majority of his time with the Princess and her relatives, but he is slowly opening up to venturing outside its castle walls to interact those with the lower class.

But the longer he spends in Cathal, he feels more attached to the Princess and her family and friends. He remains as Elabelle's companion until she is crowned Queen and married to a wonderful young man. Regardless, even after realizing that Aether doesn't need so much of his support, he simply wanders around to do his own thing. Even if he leaves the Kingdom, he is always welcomed by many.

The new blessed princess

The Spellsinger watched the Royal family grow and even extended its bloodline to those outside of Cathal. However, it wasn't until he was tasked to take care of a new, young, and valuable princess. He had been on careful watch since she was born but he was only distant from her until she grew up to become a gifted young woman.

But the whole time, Ennette would only recognize him as her butler. And he hoped he'd remain that way for as long as he can keep it but he wanted to use his powers to brighten her life again - most likely when she had been saddened with the events of her previous lover - and thus Ennette discovering his true form as a powerful spellsinger and a demigod would be inevitable.
Though even after she discovered Aether's true form, all Rythmonius wanted was to provide her happiness - and the only way he believed he could do that was to be her companion and partner until death. And when Ennette wanted to help her father, she ends up venturing outside of her Kingdom. Of course, Aether tags along as he doesn't want to be separated from his lover for long.