Another World Survival: Min-maxing my Support and Summoning Magic - Volume 2 (Light Novel‪)‬

Having freed the girls' dormitory from the orcs' clutches, Kazuhisa and the others quickly move to recover any survivors within.
Though the dead far outnumber the living, Kazuhisa's glad to have gained new members for the Cultivation Center. However, the world is cruel, and things don't always play out the way one envisions it to.
When Kazuhisa finds the Cultivation Center is under threat of being completely destroyed by an army of orcs, he's forced to consider all possibilities of survival—even if it means forming an alliance with one of the people he hates the most.