sidekick

US /ˈsaɪd.kɪk/
UK /ˈsaɪd.kɪk/
"sidekick" picture
1.

a person's assistant or close associate, especially one who is less important than that person

:
•
Batman and Robin are a famous hero and sidekick duo.
•
Every great detective needs a loyal sidekick.
:
assistantaideassociatehenchmanpartner