In the next birth, the killed living being will be born as human being, you will be born as the living being and you will be killed similarly by the human being so that your soul will realize the pain and get reformed.
Sorry to burst your illusion and hope that you will be "reborn" as a living being once your current human body dies. You won't.
This is it. Look at yourself in the mirror, and learn to love the body that God gave you. It's the only one you will ever have.
God created Man out of dust, in His image. Therefore, we resemble our Creator. The animals were created separately from man, not just for his personal use, but, to bring joy and beauty to creation. They were created before mankind. They have their own purpose - separate from man's.
Our human soul is given a human body only. We are given this body so that we can understand the teachings of the Lord, so that we can comprehend, so that we can make this world a better place. God has given us everything we need to reach salvation, culminating in His own Son. Christ has showed us the way to salvation. He has taught us all we need to know, and how we need to live.
There is NO excuse for someone to live a "bad" life. None. We live a "bad" life for our own lack of discipline. Our lack of love. Our selfishness and pride. We are here to do battle against ourselves. We are to make ourselves into the person that God had initially created us to be.
That is why in Orthodoxy we have a number of Sacraments, to help us on our journey - Baptism, Confession, Communion, etc. We have the examples of the saints to bolster our determination. If they, mere humans just like us, could attain sainthood, than I must try, because apparently it is attainable.
You have one chance. You do not get to have "do overs". This is not a board game. You know the rules, you either choose to follow them or not. You are aware of the rewards or the punishment. Your salvation is in your own hands, to gain or lose in this, your one life time on earth.
There is NO unity between your Hindu faith and Orthodoxy. Any so called faith that does not recognize the Holy Trinity is being misled. I truly hope that in time you will come to realize this. Take a moment and research the promise of eternal salvation that is offered by the Orthodox Faith.
As for "living beings" - all manner of life is God's creation, and as such it should be respected and cared for, not just the four-legged kind. ....I am certain the kirpan was never used to cause any living being any harm.