Seitokaichou Hikaru: Koukai Shojo Soushitsu

There is a school where students learn how to hunt monsters. Yuki, Seira and Hikaru finally defeat Varmus, a monster. But their battle doesn't end yet.... A new enemy revives Varmus and Kotone, their teacher, is kidnapped by him. Following it, heroines are kidnapped one by one. His purpose is actually to make them give birth to monster babies....