Byakuya Amamiya, a friendly "boy next door-eque" ninja who looks calm and collected but is fighting his anxiety and chronic pain 24/7. Out of the other older teens, he's labeled as the most responsible and is often assigned to lead. He doesn't like being in charge. Unless necessary.
VA: Mark Whitten

Husayn of Samudra, a stern and inflexible young warrior. He's driven to fight only honorably, but this leads him into conflict with Regulus, who he is suspicious of for several different reasons. He is mute but highly expressive, and it's easy to tell what he's thinking from his face.

Regulus Laplace, a charming, if slightly arrogant, young mage who deleted their gender to free up space to learn new spells. "Fucking around and finding out" is practically his modus operandi, but there are many secrets hiding behind her knowing smile.

VA I imagine: Mallorie Rodak aka Frieren