Redemption healing enemies?

An enemy Fiora was alone and I used Redemption on her and it looked like it healed her. It has a white font number above her and I can't remember if it has a plus sign beside the number.

I know true damage is a white font number, but not sure if I misread the Fiora incident.

PS: I think the sound effect for Redemption is misleading, it sounds like you're healing (which is only half true, you only heal the allies and damage enemy champions). Maybe a more neutral sound effect would be a nice implement. The user experience is a bit off in my opinion.

PS: I was playing Deep Sea Nami support (not sure if this is relevant). This is weird, boards is bugging as well.