Question: Why Does Evil Exist?
If everything emanates from Lord Krishna, why does evil exist when God is all good?
Answer: It Was Our Doing.
Since everything emanates from Krishna, everything is meant to be engaged in Krishna service. Evil become manifested when we instead try to engage the energy of Krishna in our service instead of Krishna's service. In other words, evil is the result our misuse of our free will. We cannot blame Krishna for evil. We must instead blame ourselves.