Anime Crossover Apocalypse: My Simulator is Very Unorthodox

Good news! Jingu Yi's memories have been awakened, and he has also obtained a simulator.
Bad news: Although Jingu Yi is in a crossover anime world, including [School of Silence], a zombie crisis is about to erupt.
Furthermore, due to a world bug, the male protagonist is gone, and the original female protagonist's childhood sweetheart, who was just a cannon fodder, no longer exists.
However, the simulator is quite powerful; as long as you interact with girls in the simulation, you can acquire their skills.
[Ding~ Contact with Miyamoto Rei has earned you the reward: Gun Skill.]
[Ding~ Contact with Saeko Busujima has earned you the reward: Kendo Mastery.]
[Ding~ Contact with Shizuka Marikawa grants reward: Vehicle Mastery.]
[Ding~ Contact with Shiraki Meiko has earned you the reward: Super Strength.]
[Ding~ Contact with Mai Sakurajima has earned you the reward: Invisibility.]
Using the simulator, Jingu Yi gradually grew stronger. To acquire more skills (and a harem), he eventually built an all-female shelter in the apocalypse, living a blissful life as a pillar of strength, constantly being devoured by the girls day and night.