shuumatsu_no_harem
A 2016 manga serialized in Shounen Jump+, it is written by LINK with art by Shouno Kotarou. The series centers on a boy who wakes up five years after a virus has killed most of the men on Earth, and the government's efforts to get him to directly reproduce with a harem of girls. There is an anime adaptation that was released during the Winter 2022 season by Studio Gokumi & AXsiZ.
English Title: World's End Harem