Senpai is an honorific used in Japan towards someone of a higher class than you, almost like a role model. The opposite of senpai is kohai, used towards someone that is of a lower class than you. These terms are used in businesses and wherever else there are rankings in class.
example: Itsuki-senpai, would you like me to print those documents for you?
Also, senpai DOES NOT mean your crush, I'm telling this to all of those people that think senpai means crush.
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