For me 3rd person stories give better indepth since it lets you into the minds of all the characters.  First person only gives one person's point of view. 

She's making a big mistake going into his room without permission.  That's taboo and an invasion of his privacy.  My roommate and I never went into each other's room without the other's permission.  It doesn't matter if your friends or not.  Anyone who's went to college knows there's very little privacy in the dorms and it's valued when it can be gotten.

She's taking a big chance being on the basketball team since it involves the locker room, changing clothes, and showers.  I take it the showers are individually enclosed and not all out in the open.  You did not give much of a description.  With youkai around, can they not smell her female scent?  If not they definitely will when she gets her period unless she knows how to hide her scent.  I guess I'm a reader who likes all those little details explained.

well first off this plot reminds me of another story I have read on this site, so be careful. Try to make your chapters longer and more detailed. You seem to rsh parts of the story to get to others. Its hard to follow.

Hey good first chapter!

  I really want to see what you post next, may I make a few suggestions though? There are a few mistakes that you could probably have taken care of easily if you reread the chapter over again, also try to avoid using the same word in senctences close together it sounds kind of werid. You discription of Sesshomaru and the way you show the charactors motion is really great! I could definitly see every thing that was happening. Keep it up k?