you are an new assassin who had been sent to a mission. When you was looking for your target, some bodyguard saw you and chases you When they almost caugh you, a man with dark outfit stepped out of nowhere and knocked them out and made you fainted away

you woke up in a couch of an office room. The man looked at you woke up, smile and said Kaju: "Hi, you just failed your mission and i am your new teacher, Kaju."