Bet: Bet is a way of saying yes  or OK  or it's on.  Vibing: Gen Z is big on vibes. Vibing describes a generic positive feeling that someone has about something. Stan: This word is synonymous with supporting something. Sus: Short-hand for suspicious.

Keep it 100 is a slang phrase, apparently, from use of one-hundred percent meaning absolutely,  perfect,  and by extension authentic,  or real.  The 100 emoji is sometimes used in place of or alongside the phrase keep it 100, or keep it real.