What caused Ruka to change?


What caused

> Ruka to become a girl?

In episode 8, they jokingly try to alter

> Ruka's gender to make her a girl

with a D-Mail, but what they do is scientifically crude and unlikely to do
anything.

Then, they send another D-Mail which

> changes Akihabara drastically

and it is after this change that Okabe discovers that Ruka has changed.

I thought it was the latter D-Mail that caused Ruka to change because it was
the D-Mail directly before the change was realized, when people started
behaving as if Ruka was

> a girl all along.

However, when this latter D-Mail, which had an effect on the city,

> is cancelled out,

Ruka is still

> a girl.

Was it the former or latter D-Mail that caused Ruka to change?

[Relevant
episodes](https://en.wikipedia.org/wiki/List_of_Steins;Gate_episodes):

Episode 8

> D-Mail sent to change Ruka's gender. Likely a failure as it just told Ruka's
> mother to change her diet.

Episode 9

> Faris's unknown D-Mail which changes Akihabara.

Episode 10

> Okabe discovers Ruka's gender change, spurred by how people treat her as a
> girl.

Episode 17

> Okabe reverts Akihabara to its prior state.

Episode 18

> Okabe has to revert Ruka to a boy.




It was the D-Mail Ruka sent that changed Ruka to a girl.

When Okabe sees Ruka, he doesn't realize Ruka has in fact become a girl. He
only realizes after Faris' D-Mail that Ruka has become a girl.

Also to support this, Faris' D-Mail wasn't sent that long back to have
affected Ruka's gender, as Ruka was born well before Faris' D-Mail was sent.

