[Gameplay] Viktor damageing himself bug

I was playing Viktor the other day, like 4 days ago and I noticed on the "death tab" that something from myself, Viktor, had dealt few damage to himself in his death It kind of seems rubbish but you will understand what I mean after seeing the screenshot I will attach.

I think it's some sort of bug, possibly from his ult, because I used ult right before I got killed by Kha'zix Of course there was no Viktor on the enemy team and it is after the rework of Viktor

Screenshot is in Korean but its not that hard to figure it out... but just to make sure... Kha'zix got a kill with Twisted Fate and Viktor(myself) assists, specifically 3 (1%) True damage from unknown source

Although I live in US and previously played in NA server, right now I play in Latin North but I thought it might be easier to report this here (Besides, I'm not a good Spanish speaker...) Latin username is ekzmtnrgml with Summoner name Qslit

I do not know how did this happened for sure