Similar plot where main character is in a sort of limbo where they have insight into the enemy.
They use their human and more monstrous side together.

Some of the same main cast members.
Post post apocalyptic life with humanoid monsters.
Human vs monsters

Both have to do with human transformed monsters.
Conflict on interest on whether all are fully monsters or not

Both dramas portray the Tsundere vibe, stand offish but also shows affection to their lover. They also both have aspects of school and work.

Both explore how evil spirits and evil within oneself can lead to humans attacking each other.
Uncanny Counter is a bit more light and cartoonish in delivery while Hellbound is set up more like a dystopian alternate universe.

Both shows explore the minds and actions of people. Exploring the question of what is truly good and bad and what humanity is out of these two are very deep in both shows. I think an important factor in both shows is the initial desperation for money, which in that point in time equates to survival.
The filming and vibes of both shows make it hard for the audience to tell if a scene actually happened or if it was simply a hallucination/imaginary.
I don't want to spoil the show so I can't say much more but if you like one of these you will like the other.

Unfortunately this recommendation is a spoiler.

Same messages about learning to love life and find those who care about you through a game administered by death its self.

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.

Vibes are less rom-comy but has some similar sexual tension and developing deeper romance.
There are multiple couples/ storylines in The Jungle and one does take place in an office setting.

Set in 1980-90s, nostalgia feeling in shows. Old school romance. Twinkling watermelon has a slightly more modern feel but both satisfy the romance old school vibes.

End of world monster mutation survival story. I think both have quite similar monster cgi portrayals. The main character is able to control his inner monster in some way.

Both are Dark Sexual Dramas that has multiple storylines and a flirtatious group of boys.
Playboyy has a bit more mystery and plot to the story where as The Jungle has more individual character development plot focus.
Playboyy is a BL while The Jungle has only straight couples.