Kanojo ga Flag wo Oraretara EP1 - I'm Going to Marry Her, Once I Leave This School

Flag shows the different paths that fate can take. Hatate Souta transfers into Hatagaya Academy, and he can see these flags, and control them. Souta tries to avoid people after what happened in his past, but Nanami notices something was up when Souta stops an accident on his way to school, and then another girl starts to take an interest in him.