Step-Siblings (Louis Tomlinson FanFic)

So there's this girl that I've hated for like...let's see, my entire life! And now her dad is marrying my mum and she's moving in down the hall. We both can't stand each other but our parents don't seem to care, so we try to be civil in front of them but after just a day of her walking around in whatever she wants and doing whatever she pleases, will my feelings towards her change? for the better? for the worse? will I start to hate her even more than before or will something forbidden by just about every law ever, happen between us?
Will my new Step-Sibling turn into something more? maybe...enemies with benefits?

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