Sitecore items will always coexist across language barriers. This has to do (atleast I believe this is one of the reasons) with the fact that they all inherit from Standard Template, and this template has some fields that are marked "Shared", i.e. implicitly available to any language.
What the item does not have however, is a Version in the current language. Field values will return null.
You can test this yourself by modifying the Sample Rendering.xsl to this:
<xsl:for-each select="item">
<xsl:value-of select="@name" /> ( <sc:text field="title" /> )
<br />
</xsl:for-each>
I ran a quick test, and this was my result. Sample Item 3 is created in non-context language.
Sitecore Welcome to Sitecore
Sample Item 1 ( Sample Item 1 )
Sample Item 2 ( Sample Item 2 )
Sample Item 3 ( )