Why did Nadeko use different names for Araragi?


Episode 12, the story about Otorimonogatari, contains the story Nadeko Medusa.
Nadeko said this:

> Favorite big brother: Koyomi Oniichan
>
> In Love with: Araragi Koyomi

why she said it differently? Does it mean that she consider Araragi as two
different person? Because in Monogatari Series Second Season she turn out to
be a

> yandere, and want to kill Araragi, the man that she love.




The difference emphasizes the extent of her love towards Araragi: she loves
Araragi as a big brother figure **as much as** she loves Araragi as a man.

> Favorite big brother: Koyomi Oniichan

This is the love of a sister for her big brother. _Sibling love_.

The honorific _onii-chan_ shows that she holds Araragi very dear and sees him
as if he were her real big brother.

> In Love with: Araragi Koyomi

This is the love of a girl for a boy. _Boy-girl love_.

The absence of honorific, which is a stark contrast to the previous line,
shows that she loves Araragi as a member of opposite sex, not just love
between sibling.




The difference emphasizes the extent of her love towards Araragi: she loves
Araragi as a big brother figure **as much as** she loves Araragi as a man.

> Favorite big brother: Koyomi Oniichan

This is the love of a sister for her big brother. _Sibling love_.

The honorific _onii-chan_ shows that she holds Araragi very dear and sees him
as if he were her real big brother.

> In Love with: Araragi Koyomi

This is the love of a girl for a boy. _Boy-girl love_.

The absence of honorific, which is a stark contrast to the previous line,
shows that she loves Araragi as a member of opposite sex, not just love
between sibling.

