When the door opened, Buffy looked over to see who had entered. Her slight smile turned into a slightly annoyed look when Dawn dropped the towel, and she shook her head slightly. "Nice swim suit. The girl you stole it from has amazing taste." Thief. Though she knew Dawn had raided her closet. It had become apparent when she went looking for her brown boots and then found them gone. This was after Dawn had arrived, so there was really only one answer.
The door opened again, and this time her eyes lit up slightly, in the way that was not meant for family members. She didn't know what it was about Dean. He had a blend of attitudes of guys she dated in the past. He was good looking, he could hunt, take care of himself and didn't need a military squad to do it. He knew what it was like to sacrifice everything. And she just liked being with him. When he came over she smiled, and looked at Dawn. "Dean, this is Dawn." she said, reaching up to brush a strand of Dawns hair behind her shoulders- a long time habit of hers. "Dawn, Dean." It had never stopped her one way or another before, but she did hope that Dawn liked him. Even if they weren't officially anything.
When the door opened again and Tim walked in, Buffy immediately dropped her hand away from Dawn. Buffy was aware her sister liked him, as much as that somewhat annoyed her. She was growing up, big sister was going to have to deal. At least Tim knew what Buffy would do if he hurt Dawn, as the evidence on his skin pointed out. Though now she felt kind of guilty about it.