I just realized that some of yall might not understand this AU because i dont think I explained my thinking in the actual story but heres it go:

Grian is canonically a Cod fish look alike

Jimmy is canonically a cod

Lizzie is cononically an axolotl

Jimmy and Lizzie are canonically seablings

Grian treats Timmy like his little brother

Lizzie and Grian love harrassing Jimmy as if he were the youngest seabling

In my original story, The Secretive Hermit, I made Grian and Lizzie siblings, they were royals

In samgladiators roleplay, he joked that they were siblings because they were both from england and Lizzie was the queen, thats how I came up with my idea

Grian and lizzie siblings = grian and Jimmy siblings

Seablings canon!?!?!?

Also, let's admit it here, Jimmy and Grian are most definitely similar looking. It makes way too much sense.

I just saw a fanart picture of Grian and Jimmy as cods and the comments were all talking about how they could be siblings and this was 3 months ago they realized-

Idk man, I just live the seablings and this is my personal number one headcanon