WHO IS KATARINA'S FATHER(ANSWER)

The father of Katarina is ZED. Zed began to feel sad after killing the master and decide to join Noxus because Demica won't accept him because he broke the "balance" he‘s status in noxus become higher and higher, and Katarina and Cass(forgot her name) was born. One night zed can't resist the call of the shadows so he left Noxus and join the League as a champion ZED

This story explain that why talon's q( bleed ) , Katarina's q has marks like kennen's q akali's q and shen's q , because zed has taught them these moves.