Just sometimes, like how a genius person does everything smoothly. He gets irritated when she cannot do those 'simple' techniques he instructs. By simple, she meant, not very easy.
Achis was the second strongest warrior in this world. He had the ability and capability to surpass the male lead, Lapil. The fact was, if he decided to do endeavors on the sea, he would win over Lapil's achievements. Since both of them were warriors, they lived their life to fight.
