Well before Koga fell in love with Kagome, he didn't view humans as anything more than food for his wolves. Remember, it was Koga's wolves that initially killed Rin. It was because of Kagome that Koga stopped letting his wolves eat humans and he viewed them more respectively. The other wolves in his tribe also wanted to kill her, even eat her. So that could be one possibility. Of course, Inuyasha would never let that happen. But luckily, I guess, Koga did fall in love with Kagome, which spared her life not just from Koga, but his tribe as well.