There could also be other secondary characters. Maybe some angels or humans who become involved in the situation after Gabriel leaves. For instance, if the story is set in the Supernatural world, characters like Sam and Dean might make an appearance and play a role in baby Castiel's life after Gabriel's departure.
Obviously, Gabriel and baby Castiel are the main characters. Gabriel is the one who leaves, and baby Castiel is the one left behind.
In addition to Gabriel and baby Castiel, there might be some angelic beings that are related to Gabriel. They could be part of the backstory that led to Gabriel's decision to leave. And who knows, there might be some new characters created specifically for this fanfiction to add more depth to the story.
The best chapter pointer here is Chapter 92, "Why would a 19-year-old girl read this kind of book?!". It opens with Jiang Li, lightened from any task, had plucked a few leaves from the... and closes on Finally, someone entrenched in the circle couldn't hold back and sent a....
The best chapter pointer here is Chapter 114, "I've never seen someone so shameless!". It opens with As time passed, the number of viewers in the live broadcast gradually... and closes on But just now, an uncle came and said not to give you anything to eat." Qi....
A practical answer is Chapter 136, because it turns the idea into a concrete scene. The chapter opens with A few people retraced their steps back to the place they had just been., adds pressure through For those who have not found peace in death, isn't this talisman the best..., and ends on Aunt.
If you want the clearest chapter reference, go to Chapter 151. Early on, Now it was Zhang Cheng's turn to be confused.; later, the chapter leans on The problem lies with He Yun?. By the close, I will have my assistant pay the bill., and the chapter closes with Was he...
Look to Chapter 120 for the clearest answer. It begins with Facing the sudden and somewhat strange request from Jiang Li, Director Sun..., keeps building through But, as if by some mysterious force, he still instructed his assistant to..., and lands on Drink this." Wen Jiaojiao looked at the half.
Chapter 146 is the strongest chapter-level answer because it starts from Director Sun: "???" Jiang Li smiled and said, "In the past, the show crew... and follows through on That way, they could maximize the traffic for their live broadcast..
Chapter 117 is the strongest chapter-level answer because it starts from Fragrant and cloyingly sweet potatoes and corn were out of the pot, and Qi... and follows through on Since entering puberty, his mother had exerted strict control over his....
Chapter 124 is the strongest chapter-level answer because it starts from Since there were too many points cards inside Jiang Li's barrel, Director... and follows through on No need to repeat that number three times.] [Hang on, didn't Jiang Yan....
If you want the clearest chapter reference, go to Chapter 110. Early on, Jiang Li, carrying a wooden basin, walked over to the well.; later, the chapter leans on Uncle Zhao's house didn't have a water heater, so she could only make do....
If you want the clearest chapter reference, go to Chapter 93. Early on, Jiang Li looked back and saw several aunties linking arms, walking up the...; later, the chapter leans on The leader was indeed the aunt to whom she had read fortunes this morning..