Riot: "Dammit, we forgot to sexualize our next woman champion. Wait... I know! LET'S ADD TENTACLES!"

I imagine it went something like this (Reds, please don't correct my headcanon if wrong) :

Rito Art Department to Management: "Check out this champion model we made."

Management to Rito Art Department: "I like it but... there's something wrong I can't quite place... Let me get back to you"

---

Two weeks of intense analysis and furious pondering

Management to all department heads: "I've called you all here for this emergency meeting because we've come across a fatal flaw with Illoai. She's... well, lacking in sex appeal. With the Japan server release coming up, this is unacceptable."

Gameplay department to management: "What if we added tentacles?"

Management to all department heads: "BRILLIANT!"