Kanojo ga Flag wo Oraretara (If Her Flag Breaks)

Hatate Sota is a high school boy, who has an ability to visualize "flags" for future events such as "death flag", "friendship flag", and "romance flag". Despite the flag-viewing ability, he avoids making friends with others due to a trauma he experienced in a ship submergence accident. Four beautiful girls get interested in his strange way of living, and they begin to live with him at the school dorm by force.