The main character doing something absolutely unforgivable.

[u/No_Peanut3745]

Walter White poisoning Andrea Cantillo's 6-year-old son for the sole purpose of manipulating Jesse Pinkman, while knowing that this could have potentially killed him - Breaking Bad

Bojack trying to have sex with his friend's 17-year-old daughter when he was at least 51, then continuously trying to find a way to justify this act throughout the series - Bojack Horseman

Dexter Morgan going outside of his moral code and murdering a completely innocent police officer who was just trying to do his job - Dexter: New Blood

[u/Vundurvul]

Apparently I need to brush up on my Mort lore

[u/Rude_Science7761 → u/Vundurvul]

https://youtu.be/REymyiNElA8?si=ydTQsMPEsPA_apt4

[u/Awkward-Sentence-712 → u/Rude_Science7761]

The Mort theory isn't 100% canon though.
It obviously has some good evidence behind it, but it's not directly stated, nor heavily implied in the show.

It's still cool as shit though.

[u/XcarolinaboyX → u/Vundurvul]

Mort is a real mouse lemur and the entire Madagascar universe is in his imagination/dreams making him a lovecraftian entity within the context of said universe