King's Proposal, Vol. 5 (light novel)

When Mushiki Kuga misses Void Garden-s magicians- aptitude exam while subduing annihilation factors as Saika, he receives a notice that he will be held back. To make sure he can move on to the next year, he is made to take a week of supplementary lessons at Nirai Island under Erulka-s guidance. But there, Mushiki soon discovers that he will have more than just his grades to worry about...because everyone else who-s come to the island is trying to seduce him! It-s time to avoid expulsion and protect his chastity!