Kannazuki's fingers tightened.
All five fingers clenched the hem of his coat.
He didn't answer.
Ryuk tilted his head, his gaze shifting from Kannazuki to Jiang Shiyu, then back again.
"I've lived for thousands of years. Before you were even born,
I let other people use this notebook.
I've seen plenty of humans use it.
Everyone who gets it changes in the end.
Some become arrogant, some become cold, and some become monsters.
You're smarter than all of them, so you've changed more slowly than any of them.
But you're changing.
You care less and less about other people's lives, except hers.
Have you ever thought about how long that 'except hers' can last?"
The heating pipe clanked again.
Jiang Shiyu rolled over, mumbling something like "No more exams, no more exams," and buried her face completely in the crook of her arm.
Kannazuki looked at the stray hairs scattered across the back of her head and unclenched his fingers.
"Done asking?"
"Done."
"Then don't ask again."
His voice was so soft that even if Jiang Shiyu had been awake, she might not have heard him clearly.
Ryuk opened his mouth, but for once, he had no reply.
He flipped himself off the pipe and drifted to the window, pressing his face against the glass to look outside.
The silence lasted a long time.
Ryuk lay across the windowsill with his back to them both, looking at something outside that neither of them could see.
After a long while, the death god spoke, his voice much lower than usual.
"Sooner or later, you'll have to choose."
"Her or the notebook."
"You can't choose both."
The heating pipe fell silent. The whole building fell silent.
Kannazuki withdrew his hand from the edge of the mattress and rested it on his knee.