After the Teleportation Incident wrought by the Mana Calamity in season 1, Rudeus and Eris were abruptly thrust out into the middle of the Demon Continent, the toughest place on the planet. Surviving through this hellscape and making it back to their homeland has accelerated their growth, not only as a person but also in their trust and shared affection for each other.

During her time with Rudeus, Eris still exhibits her violent tendencies, but she has undergone significant changes throughout their journey together. Interestingly, she is also your textbook tsundere.

Furthermore, Eris and Rudeus share a mutual inferiority complex, each assuming that the other is more exceptional than themselves. This dynamic often leads to misunderstandings between them.

In contrast, Rudeus consistently maintains a demeanor that is cool, calculated, and polite when interacting with others. He thoughtfully assesses situations before taking action and always takes into account how his choices might impact the broader context. In a way, Rudeus, and Eris almost perfectly complement each other.

And the love they have shared for one another finally culminates in a Cathartic moment – when Rudeus and Eris finally get to be intimate and passionate with each other. This becomes a poignant memory in both their lives, something which both of them still crave very dearly.

Nevertheless, Rudeus’s world was chaotically overturned when Eris chose to leave him, leaving behind a painful letter in which she conveyed that they weren’t compatible. The profound impact of her departure sent him into a tumultuous emotional storm, rendering his heart irreparably broken.

What could be the reason that Eris left Rudeus out of the blue?

Why did Eris leave Rudeus?

Following a heartfelt night spent with Rudeus, knowing it would be their final encounter, Eris silently left the next morning alongside Ghislaine. Rudeus eventually found chunks of Eris’ hair on the floor and a letter on his desk saying, “You and I aren’t well-balanced right now. I’m going on a journey.”

Having witnessed Rudeus’ fatal encounter and death at the hands of Orsted, the Dragon God, Eris was filled with horror. However, what truly haunted her in that moment was her own powerlessness to shield Rudeus, leaving an enduring wound on her heart.

Rudeus was eventually resurrected when Orsted healed him upon Nanahoshi’s request. However, Eris continued to struggle with the overwhelming burden of her helplessness, a constant reminder that she believed she couldn’t be with Rudeus.

Eris had an epiphany that she had relied on Rudeus for most of their journey and didn’t want to remain dependent on him. She yearned to become strong, to be of value to him, and to stand by his side. Hence, she made the choice to depart with Ghislaine in order to embark on warrior training.

Eris’ decision to leave Rudeus can be attributed to various factors, but one reason in particular stands out. During their final night together, Eris noticed the size of Rudeus’ hands, smaller than hers. Despite being older than he is, she has taken everything he did on their journey for granted.

Eris understood that she wasn’t on par with him, driving her determination to undergo training so she could stand beside him as an equal.

Before she decided to leave, she told Rudeus that her only wish was for him to become her family, and after spending the night together, she left unannounced.

After leaving Rudeus, Eris embarked on a journey to the Holy Land of the Sword, following Ghislaine’s recommendation, to hone her skills at The Sword Sanctum.

There, she dedicated herself to rigorous training in the mountains, studying under the guidance of the Sword God, Gal Farion, and mastering the techniques of the three swords of the North God.

Her unwavering determination led her to attain the prestigious rank of Sword Saint.

To answer in short; Eris left Rudeus because she wanted to be stronger on her own rather than relying on him for everything. Eris’s decision to part ways with Rudeus was driven by her determination to undergo self-improvement.

Will Eris come back to Rudeus?

Yes, Eris returns/comes back to Rudues to aid him in the battle against the Dragon God.

With Eris’ newfound mastery of swordsmanship and personal growth, she aspires to reunite with Rudeus in the future. Her goal is to protect him, fulfilling the vision she had when she embarked on her transformative journey.

Eris eventually makes her return after Rudeus successfully rescues most of his family. Originally intending to reunite with him at the Ranoa Magic Academy, she receives a letter from Rudeus that reveals he misunderstood her departure as rejection.

Rudeus in the letter very bluntly explains his current circumstances that he is already married and has two wives. And that if Eris were to return to him, he would be willing to accept her as his third wife. In addition, Eris notices a post-script where Rudeus states that he is setting out to fight the Dragon God Orsted and that he may not survive the encounter.

Eris, along with Ghislaine, quickly rushes to Rudeus’ aid in his battle against the Dragon God, marking their long-awaited reunion.

Shortly after this second encounter with the Dragon God, Rudeus marries Eris.

Although Eris had undergone rigorous training during her time apart from Rudeus, she still grapples with an inferiority complex, feeling inadequate compared to Rudeus’ other wives. Fortunately, both Sylphie and Roxy warmly welcome Eris into the family.

Conclusion

In summary, Eris chose to part ways with Rudeus in pursuit of a transformative journey aimed at gaining strength and power.

Her primary motivation for leaving Rudeus was her unwavering determination to become strong enough to protect Rudeus, the person she held dearest in her heart.