Operation Love

Ken returns to the past wherein they met Tada-sensei, Rei's groom. Ken tried his very best to avoid making Rei and Tada-sensei close. But in the end, it was Tada-sensei who made him see the smile he never saw 6 years ago.

Ken returns to his highschool graduation where boys give their second button to the girl they like. He gave his button to another girl making Rei disappointed. He gives his best shot in order to touch Rei's heart.

Ken is given a second chance to let Rei say goodbye to her grandfather.

Ken returns to just before Rei's birthday and also on her eve of her major architectural project.

Ken returns to a fireworks festival before Tada confesses his feelings to Rei.

Ken returns to their past celebration of new year's eve. He intentionally let his friends go and see the new year's sunrise by themselves, hoping that he would forget all about Rei.

Ken returns to just before Tada proposes to Rei.

Ken returns to the last photo of the slideshow where they are in Tada's party, Tada introduces Rei to all his friends. In the middle of the event Ken dragged Rei into their elementary school.

Ken plans to have a "coming from behind victory" over Rei, but as he heard Rei's opinion about regrets, Ken decided not to change the past but to act in the present. So Ken returns to just before he has to give a speech at the wedding banquet.