Atheists!! What's the logic behind your existence..?

Something to do with roses and cabbage.

Or in English speaking countries with birds and bees.

My bad. I thought there were no theists cruising for a bruising. 

No logic required. We are all born ignorant of everything. We discover one reality after another as we grow older. Most of us discover the reality of God. Some of us don't.

Why do things need a logical justification to exist?

When a male and a female match on tinder....

Atheism is the lack of a belief in God, in my case because theists have failed to satisfy their burden of proof. Your imbecilic question is irrelevant to atheism. 

Logic is a science that deals with the principles and criteria of validity of inference and demonstration, it teaches the principles of how to reason. 

Premise #1 your question is imbecilic

Premise #2 You asked the question

Premise #3 You were sincere when asking the question and not joking.

Conclusion: therefore you are an imbecile. 

See that is what a logical argument looks like. 

Their faith is literally sealed away in acceptance.

My parents had sex, and I was born nine months later. I'm not so egotistical that I demand some grand cosmic significance to my existence. The people with huge egos end up in religions that feed their egos.

Reality.

You?           

To find truth and live with purpose. And religion is not for that. Religion is far away from the truth.