Read Author's Thought
Ryuki was scared for a moment. He never thought that world-class could send people away in the blink of an eye. Not only that, but he sent so many people away, erased their memories, healed the girls, and made sure such a thing could not happen again.
If a world-class gifted person had such power, then Ryuki really was scared for a moment, but then he calmed down and understood that he had to become world-class.
It's not that he didn't want to be before, but now he just has a greater desire to be world-class. Simply because he wants to protect himself and his loved ones.
Ryuki returned home and spent some time alone in his thoughts, sighed.
Well... Tomorrow is a holiday, so let's meet Yui, my lovely slave, tomorrow.
Ryuki thought, and he decided not to think of getting stronger or people who were stronger.