"Bubai" is an expression. People are called "bubai" if they want to avoid an uncomfortable conversation by using misleading information about something that's not related to the current subject at all.
1."Don't be a bubai all the time. I know you're trying to change the subject".
2. -Where were you last night?
-You look so pretty! Is that a new dress?
-Well thank you! Oh no, you didn't! Stop being bubai, that ain't gonna work.