...where MC got isekai and was found by the teachers of the military/knight academy, she then works as one of the staff of this school where pre pubescent / knight-to-be kids start to slowly trust and fall for her. Suddenly she returned to Japan then got isekaid again and found out years have passed in this other world. The kids are all adult and an epidemic killed the majority of women so the government decreed all women should have at least 5+ husbands. MC discovered the kids had a crush on her and now that they are adult they force her to marry all of them.
...where MC got isekai and was found by the teachers of the military/knight academy, she then works as one of the staff of this school where pre pubescent / knight-to-be kids start to slowly trust and fall for her. Suddenly she returned to Japan then got isekaid again and found out years have passed in this other world. The kids are all adult and an epidemic killed the majority of women so the government decreed all women should have at least 5+ husbands. MC discovered the kids had a crush on her and now that they are adult they force her to marry all of them.