Luna was sharing her room with her boyfriend, Neville, and  of course  they would have welcomed Hermione into their suite - but the witch could not find it in herself to crash their obvious planned week of sexual debauchery. Harry and Ginny were out of the question. Blaise and Pansy - which Ginny had befriended in due time, were shaking up as well, and the rest of the guests, including Ronald who could not make it this week, would arrive later that week for the ceremony. 