Fixation

Shikamaru Nara at a young age found his fixation in one Naruto Uzumaki who remained oblivious to his situation when it comes to tethering oneself to such a reckless person. But he learns the hard way when his fight with Sasuke at the Valley of End winds up with him winning but dying for the briefest moments.
Now knowing of the bond Naruto has chosen to stay by Shikamaru's side for better or worse.