Trust me ;^)
Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Threats to Ahri with this build
|Lux||Lux can bind you but if she does just charm her as most luxes love to proc their passives|
|Karthus||No mobility and zhonyas works well against him|
For me runes are always about damage early. The damage from the flat ap runes gives a slight advantage in damage when you are in lane and can sometimes win the lane for you.
Creeping / Jungling
Jungle Ahri is is an interesting playstyle. You have to kite with the movement speed your Q gives you. Very mana hungry and needs most of the blues. Very weak to counter jungle though. Ganks revolve around you landing your charm as your only cc.