Line Between - Alex Karev Fanfic
51 parts Complete Mature{COMPLETED} When Derek Shepherd calls his younger sister Ella to Seattle for a rare case, she plans to consult and leave. Quadruple board-certified and studying Neuro, she's used to pressure - but not to Alex Karev.
He sees her as too perfect. She sees him as infuriating. Somewhere in the chaos of Seattle Grace, they find themselves walking the line between rivalry and something much more dangerous.