Responses
It's mostly Alberu and Rosalyn who takes the lead in their group whenever Cale wasn't around. Especially during the war. Alberu is the Crown Prince of Roan Kingdom and thus it's representative, while Rosalyn was some sort of ambassador for the Breck Kingdom and the Head of the [unofficial] Magic Tower. That's why they're always together.
Rosalyn here looks like cale's sister because of the hair but i hope they would have more distinctions in the webtoon as stated in the novel. Also am i the only one who ship Rosalyn and Alberu