That looks more like Caren Ortensia rather than Illya.
Is this from Fate/Hollow Ataraxia?

Nah, Caren's hair is different.

Someone please tell me this is as innocent as it looks!

That's definitely Ilya.
And it's only 'innocent' if you haven't played the game/seen the series and don't know how Ilya thinks!

I don't think she want to transfer shirou's soul into a doll/anything alike anymore, so it's pretty much innocent.

I meant, please let there be no "mana transfer".
But yeah, thanks sartek.

This is why we need an Ilya route. Even if you skipped the sex and pissed off the lolicons, you could develop an awesome (platonic) brother/sister relationship between these two; think Heaven's Feel but a different lead heroine.

From what I recall from beast's lair she just see Shiro as her younger brother, not a love interrest so "mana transfert" is unlikely to happen.