I remember I once encountering such a word but I cannot recall it now. Could anyone please help? Thanks. Some people are very annoying because they always say they know somebody and how good their relation is. In fact, that guy is just so so. It is just like bravado.
This is called "name-dropping" the metaphor is that people "drop" names of people into conversation.
A more formal word is "ostentation" (or the adjective "ostentatious"): showing of money or power to impress people. It has a related meaning, but not exactly the same, as it can be about other things besides saying you know somebody.
While people who name-drop or are ostentatious are annoying or pretentious, I would not call them "disgusting". People who are cruel to children are disgusting. Name dropping is a lesser wrong.