Both of the main leads go back in time to prevent the death of their significant other. In both dramas the past and present selves of the main leads exist. They both fight against time to create a happy ending for the two star crossed lovers.

In both shows the male leads realizes his feelings for his long time best friend first but is afraid to confess because they are afraid that once they break up they can't be friends anymore.

Both of the main characters go back to the past to save someone who died. The story also takes place in a school setting and is an angsty story as you know the person you like will die.

In both of the shows the male lead time travels to the past to save the female lead because she always dies in the future.

They are both stories about how high school friends like each other but stay as friends for a long time because one of them is always with someone. Even when their with someone they are always there for the other person. The couple ends up dating after one of them has the courage to confess to the other because they don't want to lose their best friend if they break up.

Both of these shows include star crossed lovers who just couldn't end of together. They also both had tragic endings.