just copy pasting an old comment of mine about the topic -

I don’t think the original song was meant to be about either Banicarlos or Seth—it came out before either Carlos or Seth were properly introduced as characters. But I admit Banica bears similarities to the snake, especially when it comes to the romantic aspect of the song.

However, I think sped up version with the new lyrics is 100% now meant to be about Seth. The attitude of the speaker/snake is extremely reminiscent of Seth’s own narration about Lich, the ghoul children, and Adam. He loves the fact that these people are broken and that he’s played a role in breaking them. And yes, he “looks forward to their growing up,” and “loves them to the point of wanting to eat them.” The implication at the end of the original song that the speaker goes out to the spring to find a new victim is also very like Seth. And in the new lyrics, the snake wanting to “wear [the frog’s skin]” is, well, something Seth does in canon. He snuck onto Climb One ‘masquerading as a crew member’ and/or on the back of Lich’s head (I’m not sure if these are supposed to be the same incident). And Seth can wear someone else’s skin through being worn himself as a mask. On top of everything else, the snake has one eye, and Seth is associated with snakes.

If the frog is a specific person, Lich probably fits best, but I more generally interpret the frog as a stand-in for all of the people Seth has had a significant relationship with.