My Hero Academia: One For Him, All For You

You are the first born son of All-Might and the elder brother to Izuku. When your little brother chooses to become a hero like your father, You are helpless to stop him as he puts himself in danger. You tell yourself that you are perfectly content with ignoring the hollow ache inside and staying at the sidelines as a kind and supportive older brother.
That is until a meta human ability of your own awakens within, and gives you the ability to fill the emptiness in your life with power.
Despite being raised with the morals of a hero, you find your instincts fighting against the values you've been raised with. After all, how could an average guy like you resist taking whatever he wants? Especially since that rainbow glow of a Quirk inside your little brother would fit so nicely alongside your growing collection.....

{Content Warning: Blood, violence, murder graphic depictions of violence, mental instability, mental health issues, unhealthy relationships, obsessive behaviour, platonic yandere, implied addiction, dark protagonist, dark themes, corruption, light sadism}

A/N: The reader is put in the character of an unrepentant villain so please proceed with caution! That being said there's lots of brotherly fluff and family bonding so it's not all bad :)