Since I haven't read Volume 12 in detail, it's hard to name the exact new characters. However, based on the trend of the series, new characters could be introduced to further complicate the main character's life. They could be characters with their own agendas, like a mysterious merchant who has some connection to a powerful magical artifact that the main character is interested in. Or it could be a group of adventurers who cross paths with the main character and they end up having to work together to achieve a common goal.
I'm not entirely sure which new characters are introduced in Volume 12 specifically. But it's common in the series for new characters to be related to the main character's new adventures or challenges. They could be fellow students if he's at a new school, or locals from a new place he visits.
I'm not sure which new characters are introduced in this volume specifically. It could be characters related to the new areas or story arcs that start in this volume.
I'm not entirely sure as I haven't read Volume 8 in detail yet, but there could be some characters related to the new places Rudeus visits. Maybe a new mentor figure for his magic studies.
It's possible that there is a new love interest introduced in Volume 9. This character could be someone who is quite different from the protagonist's previous relationships. Their relationship could develop in a way that tests the protagonist's maturity and understanding of love, while also adding a new layer of complexity to the story's overall narrative.
There might be a new mentor - like figure who has a unique perspective on magic. Maybe there's also a new rival, someone who challenges the main character in his pursuit of knowledge or power. These new characters would add more depth and variety to the story.
There may be a new teacher figure who plays a crucial role in the protagonist's magical training. This character could bring in new techniques and knowledge.
The main character is Rudeus Greyrat. He is a NEET in his previous life and gets reincarnated in a new world in this volume.
The protagonist is surely an important character. His actions and decisions drive the story forward. There may also be his friends or allies who play crucial roles, like those who have been with him since the earlier volumes and continue to support or challenge him in this one.
The main character is Rudeus Greyrat. He is the one who gets reincarnated.
There's Sylphiette. She is one of Rudeus' friends and later love interests. She has her own growth arc and her relationship with Rudeus is a key part of the story. Eris Boreas Greyrat is another important character. She is a noble and has a feisty personality. Her interactions with Rudeus are full of energy and she also plays a role in his development.
There is also Eris Boreas Greyrat. She has a complex relationship with the protagonist and plays an important role in his development and the overall story.