Ethically what is the absolute latest Clark can wait to tell Lois the truth?

[The World]

By truth I mean that he's an alien from space. I think even we can all agree by the time she's pregnant with his child it's too late.

[manwhohaseverything]

Before proposing to marriage or having her move in.

[Laufeyson]

When he wanted to advance their relationship once and for all.

[lotchj]

He should tell her before the relationship becomes serious!! Being honest and upfront is always the best!!

[NaVi]

They start dating: the normal thing is that clark starts dating girls in high school, if he told every girl, there would be no secret.
sex: more of the same, then NO.
marriage: they are supposed to share a life together, so YES.
But you have to keep in mind that Lois has secrets even when you're married, so Clark has no obligation to be honest.

[bat39]

Before proposing marriage, at the latest.

[Vordan]

Before proposing marriage, at the latest.

This is the absolute latest for me as well.

[lotchj]

They start dating: the normal thing is that clark starts dating girls in high school, if he told every girl, there would be no secret.
sex: more of the same, then NO.
marriage: they are supposed to share a life together, so YES.
But you have to keep in mind that Lois has secrets even when you're married, so Clark has no obligation to be honest.

If that's the case with Lois, What's the point of being in a relationship with her ??? If they can't be completely honest with each other, which means no secrets!! What's the point??? It's ashame how sex has been de-valued today!! It's like a hand shake, what ashame!!!

[PCN24454]

Naturally, when he's telling her that he's Superman.

Most adaptations don't "Superman being an alien" as a secret, so the main secret is that he's Superman.

In "Lois & Clark", Lois initially turned down his first proposal because he wasn't really ready to open up to her, similar to MJ turning down Peter.

[NaVi]

If that's the case with Lois, What's the point of being in a relationship with her ??? If they can't be completely honest with each other, which means no secrets!! What's the point??? It's ashame how sex has been de-valued today!! It's like a hand shake, what ashame!!!

Like it or not, nowadays it is normal that sex is just sex, you cannot tell your most important secrets (clark's secret puts his friends and family in danger) to anyone. I understand that there is talk of whether clark acts well or not by keeping his secret from lois, but we must not forget that in a relationship there are two people, and the relationship must be judged by the actions of both.

[MyriVerse]

If that's the case with Lois, What's the point of being in a relationship with her ??? If they can't be completely honest with each other, which means no secrets!! What's the point??? It's ashame how sex has been de-valued today!! It's like a hand shake, what ashame!!!

Holding off on sex too long devalues it more, imo.

Anyway... I don't think telling every significant girlfriend would render the secret gone. The latest would definitely be before sex.