Across all parallel universes, the 'Sanjeon Geumcheon' series is a hit, featuring the protagonist Geumcheon, the main and supporting cast, and even spin-off comics and light novels about Geumcheon's son, Do-jun. The anime currently airing on TV is 'Sanjeon Geumcheon: Aerial Battle' Seasons 3 and 4.

The Author's Mom works as a housewife while fulfilling her high-level Archangel mission of maintaining order among non-humans and spirits. The Author's Dad, a former peak-level demon, works incredibly hard as the CEO of a top-tier SME. The reason they work so hard despite the exhaustion is for their family—especially for their eldest son, the Author, who was originally meant to be an only child.

So, how were the second child Gyeong-seon and the third child Bok-jin born?

On the day of fate, a malicious patient mistreated him, causing his chains of self-control to break. His power as a fallen angel manifested, and he nearly killed the patient, but his parents stopped him. Myeong-ho lost consciousness and, within his mind, achieved a temporary victory over the powerful unborn entity that would become the second child. After a long hospitalization and discharge, he trained and exercised. On a second day of fate, facing death at the hands of a criminal syndicate, he successfully negotiated with the unborn entities. Myeong-ho became a fallen angel known as 'Author.' Over time and through many battles, he reached the level of a Multiversal God. He then transferred the souls of the two unborn entities into a recently deceased dog and cat. The dog became the second child, Lee Gyeong-seon, and the cat became the third, Kim Bok-jin. They were given names and identities, capable of transforming into human, demi-human, or fallen angel forms at will.

Now, witness the chaotic daily life of this multiverse-scale family of troublemakers.