The job description offers 1 day of work (up to 8 hours total) with a per diem compensation of 30,000 yen ($266.16 US) plus transportation expenses.
Successful applicants will also see their names in the credits of Overlord: The Undead King and / or Overlord: The Dark Warrior.
The job description also notes the part-time gig also offers valuable behind-the-scenes experience in the profession of voice acting, that on-site acting coaching will be provided before recording, and that no experience is necessary to apply.