The Villain Has Reincarnated To Commit One Last Sin

I committed many evils and caused suffering to many people.
I turned my back on the Empire I swore to protect with my life.
I murdered children to gain recognition for evil.
I forcibly raped women.
And... I slaughtered my entire family just to get power.
When I accomplished my task of defeating the Demon King, I ended up in a near-death state.
I laughed at the situation I found myself in. However, I did not despair... Before losing what little vitality I had left, I managed to successfully contaminate the 'Hero's Inheritance'.
And along with it, the darkness finally consumed me. But, I didn't die, but I went back to the past.
[The 'The Essence of False Sin' System has been unlocked!]
Due to the bad deeds I did in my previous life, I was given a new power. With this new life and the 'System' given to me, I will do my best to defeat the Demon King again.
But... A big obstacle will appear in my way...
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The cover drawing does not belong to me. I'm using it for the moment until I finish drawing my cover...