is the snake really the deity brother?

Maybe not

i wish they will explain it a bit more

Maybe its Just like brotherhood relationship between friends

haha! it was a joke, right?
what kind of normal friend whats to bite their neck so intensely

But, after read the raw, i think the snake had an interest to the deity is only when they were a kid, and now he looks like have special interest in the deity's child. And, the snake is really strong and like to bully the deity, maybe thats why the deity is a bit scare of him. But they were already be friend since a long time, and beside his evil personality, the snake is a good friend and big bro. Thats what i can conlude from the raw, maybe there're some mistake, coz i don't understand the language, just tried to understand by the art. Ah, and for the bite and sucking blood, maybe its just the way deities to get power. ╮(￣▽￣)╭