[WhiteWings]

Not really a spoiler but just in case for those not seen episode 22 yet...

Spoiler:

Nah, it's unlikely the series is going to be merciful enough to mercy kill Euphemia. At least not right away. I think she’s going to linger and seriously haunt both Lelouch and Suzaku for a while.

There’s also a chance that she’ll at some point come back to her senses and be seriously traumatized by what she’s done even if she has no actual memory of them.