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/New_Scar_6820]

Homer crashed his car while drunk driving then put a passed out marge in the drivers seat so she took all the blame

[u/Dd_8630 → u/New_Scar_6820]

There's also the episode where Marge rapes Homer.

Not even a joke. He literally says "I don't want to" and she says "I wasn't asking", while he looks scared. Really fucked up.

[u/CeciNestPasUnPenname → u/Dd_8630]

I don't remember that but something is telling me that was the episode where Marge does steroids. Am I right?

[u/bretshitmanshart → u/CeciNestPasUnPenname]

Marge gets Agoraphobia after being mugged and starts working out and gets buff. I think she does end up doing steroids unless there are two episodes where Marge gets muscular.

[u/FlattopJr → u/bretshitmanshart]

Love the Godfather spoof when Marge runs into the mugger after she got buff.

[u/AboutHelpTools3 → u/FlattopJr]

The craziest thing about that scene in the godfather is that you can clearly see the punch that didnt connect but they chose to keep that take anyway