Why Kuroko Shirai is the best

Because she is.

 

Ok other than that

i know most people hate her because shes clingy to Mikoto Misaka, but we know she really cares about Misaka, like we see it most in the sisters arc and when she lost her memory

shes truly a blessed pickle

  ALSO her friendship with Kongo is just fbhibieb in the 2nd ending of railgun t we can see them playing chess

 AND her esper power is so cool and shes so smart and her fighting skills are GoLd, for example when she went against Mitori, the fact that she blocked the knife with her hand instead of teleporting is because she knew her oponent knew she could teleport so why would she throw a knife at her? its like shooting a slenerman in minecraft, impossible to hit them, the only difference here is that Kuroko cant immidiatly teleport right after she telepoted so with the second knife midori could have hit her