1. Answer: It depends on everyone's taste and these rankings change all the time. According to RankMyPorn, at the moment, the top ranked 18+ Teen Female Pornstars in the world are: Kenzie Reeves, Veronica Leal, Elsa Jean, Jessa Rhodes, Jessie Rogers, Trinity St.Clair, Kendall Karson, Kiara Lord, Jewelz Blu, Emily Grey, but these will change based on what people vote.
2. Answer: It changes. You can see the latest rankings on RankMyPorn.com and also vote on it for free.