[HELP] Finding this manhwa

I've organized the information I have into sections.

- Muted orange-haired protagonist wearing a suit.

• Black or Grey-haired male lead who wears dark clothes and gloves.
• Monster or Zombie-hunting company. (Not sure what kind of creature it was)
• Monsters infect humans.(?)
• Protagonist is transferred(?) from a bigger company.
• Company is run by two cousins, one of them being the male lead.
• Protagonist has a crush on the blonde.
• Male lead is rumored to have inhuman strength and there are suspicions he might actually be a monster.
• Protagonist secretly writes a romance web novel that everyone at work reads.

Thank you in advance.