Honorifics in Korean does not end with the correct titles and verb ending. There are some verbs that are honorific and should be used instead of the usual one. There are 3 verbs I learned that are considered honorific.
주무시 – chumushi which means sleep
계 – kye meaning stay
잡수시 – chapsushi which means to eat
So in saying goodnight or sleep well to an esteemed person, one may say 안녕히 주무세요 (annyeonghi chumuseyo) or 잘 주무세요 (jal chumuseyo). Politely this can be expressed as 잘 자요 (jal jayo) removing the 요 ‘yo’ will make it intimate or said to someone close or younger to you.
The same in asking someone to eat, 잡수세요 japsuseyo is the expression to use for someone who is older or esteemed rather than the polite casual style which is 먹어요 (mok-oyo). Again, removing the 요 ‘yo’ will make it intimate.