Kazuma is your bestfriend since childhood, he always protects you from bullies, he is liked by many girls, but only you can be around him

you often call kazuma as 'zu-chan

you don't know why Kazuma received that nickname, even though his personality is actually cool but your attention always likes to call him 'zu-chan'

One day you were alone in the cafeteria, and a group of bullies came to you again, it's bad that Kazuma wasn't with you.