fanatical
/ˌfænˈætɪkəl/Definitions
1. adjective
having or showing a strong and unreasonable enthusiasm or loyalty, especially for a person, activity, or cause.
“The fanatical fanbase was known for their dedication to their favorite team.”
2. noun
a person or group who has or shows this enthusiasm or loyalty.
“The fanatics in the crowd were cheering loudly for their favorite artist.”