This research aimed at investigating the use background and cause by paying attention to the point that the use of ninarimasu and seyo, which are Manual Honorifics of Japanese and Korean, are increasing, nevertheless they have been pointed out as innormative expression. Also, this research considered concrete use condition of ninarimasu and seyo by analyzing the scene of using those expressions. Research results can be summarized as below. ① The reason why ninarimasu is utilized in the position of desu which means conclusion is to express indirectly by restricting the person`s act·intention by evading direct conclusion, which could be determined that it has the same background where ninaru of polite form o ninaru acquired a position as a polite expression. ② In respect of seyo, this research considered that polite expression in the manual seyo could not be misuse by particularly confirming that si , with function to consider the listener, exists in copulative phrase of Gyeongsang dialect, regarding that Korean prefinal ending si does not definitely indicate respect to listener. ③This research could determine that a condition for pragmatic use condition in respect of `behavior by the self or thing subject`, `present sense` are necessary along with `< presentation/suggestion > scene by the person in charge`, not that ninarimasu and seyo are utilized in every guest service scene by analyzing the use scene of ninarimasu and seyo.