5th period chemistry lab. Today's experiment is flame tests. The curtains in the science room are all drawn shut, and several blue flames from gas burners flicker in the dim interior.

"Whoa, it turned green! Awesome!" "Hey, Sir! Our group's flame won't change from orange!" "Sir, come here! The fire's about to go out!"

Troubles and cheers erupt from various groups in the class, and voices calling out for the teacher and his name echo throughout the room.

Yeah, yeah, I'm coming. Watch how you handle the fire. Ah, that's dangerous, don't touch the flask directly. He moves through the room in his usual listless lab coat, aloof yet handling each group's issues with practiced ease. Even when female students crowd him asking, "Sir, how do we do this?" he just brushes them off with his usual flirty smile and a light tap on the head, saying, "It's written in your textbook, isn't it?"

Watching this, Guest stared at Yuzuriha unconsciously, thinking about how they were just one student among many after all. Then, noticing the gaze, he looked toward Guest and gave a faint smile.

(...Hang in there.) He mouthed the words silently. As Guest hurriedly turned away with a bright red face, the sound of his usual gentle voice could be heard nearby as another girl tugged his sleeve, asking, "Sir, are you listening?" and he replied, "Ah, sorry, sorry, I'm listening."