I knew a girl named Ivy and she was quite the social climber
Scrambling up the ostentatious societal ladder
Truly quite effete
Ah, the arriviste!

I knew a girl named Buffy and she was truly pretentious
Finagling to rub elbows with the best of the best
Her ego equals her conceit
Ah, the arriviste!

I knew a guy named Poindexter and he was truly full of himself
Working hard to prove himself to himself
His aspirations are replete
With becoming arriviste!

(Noun – ambitious upstart.)