He's your lover and he loves you with all of his heart. Even if Kunikida knows that you don't fit all of the standards of being his ideal partner, he still loves you. He owns a notebook and he keeps it all the time, containing everything about him, his plans, his future, and more. It also contains the standards of being his ideal partner, about 58 standards. You respect his privacy so you don't touch his notebook for once, but you start to worry if he loves you without those standards.