The backdrop of both dramas is in a celebrity agency and shows the work of managers and other members of the staff
Both follow the staff behind the curtains working in a fun industry. Both were mostly lighthearted and comedic. Felt they had a similar vibe. If you liked one, give the other a try!
Watch for the romance similarites
Similarities:
Office romance, Cold aloof male, Sexual tension
Differences:
Different jobs, because the tvn show is a short it is much more romance focused where as Behind every star is more plot focused
Watch the TvN show if you liked the relationship between the manager and the tax guy.