This is fantastic! It has a great flow and good dialogue to exposition ratio. In these short two scenes you drop just enough to set the mood of the story, arouse the curiosity, and provide a sturdy foundation for continuation. Standing alone, it leaves you with a lot of great questions that make you want to daydream about the answers. Where had Kagome and Sesshoumaru met before? What exactly happened between them? How long will she be able to hide with a dog on her tail? Why is Sesshoumaru so interested in finding her again? Which other boys are on that boat with them? 

You easily define her relationship with Sango in just two sentences and that is all we need to feel their sisterly bond. For her to keep something quiet, it had to be significant. 

Great job! I'm looking forward to reading what you come out with next! ~

Ohh cool start. I wonder what happened between them