Classroom of the Elite: Year 2 (Light Novel) Vol. 4.5 (novel)

The exam is over and the students' summer break has started aboard a luxury cruise ship! Unfortunately, it's not all fun in the sun. Ryuuen is on the hunt for the person that attacked Kinoshita and Komiya on the island, and for some reason, the entire third-year class seems to be watching Ayanokouji very, very closely… Can everyone enjoy their vacation despite the rough waters ahead?