Prologue

Wall Sina,

Though known most for being the interior wall and the most wealthiest one of all, lies an Underground City beneath. Where it was the complete opposite from above.

Before he was Humanity's Strongest, he was just a thug from the Underground City.

And she was known as the Underground's most Ruthless.

He was quiet

She was loud

He was serious

She was sarcastic

Both complete opposites but one thing in common,
They were crazy for each other...