Steve

Is named Steve. Believed to be human, though unconfirmed.

Unfortunately, Steve is known to have left the band, despite adding 2 songs to the set list.

He had an unnamed girlfriend, with whom he broke up with shortly after quitting the band.

He also plays, or he used to play rhythm guitar.

Steve is never shown but Rudy and his bandmates talk about him in the following videos:

When your guitarist can't stop playing during breaks

every guitarists first day in the studio

every drummers first day in the studio

every singers first time in the studio

every band rehearsal ever

how to be a successful musician in 2019

guitarists tries playing outside for the first time (this is actually an add)

when your band is trying to come up with a name

every singers first band audition