Vince Fontaine was a radio announcer, first heard during the animated title sequence. He is played by Edd Byrnes in the 1978 movie, and by Mario Lopez in the 2016 Live Performance.
Jeannie From The Ellen Show Plays His Assistant in "Grease Live"
Vince uncomfortably flirts with Marty, who is likely half his age. He also makes a pass at Principal McGee during the dance.
Marty ditched him after she caught him slipping aspirin into her coke.