Munto

i dont know how 2 Xplane but they look simular,like the world and the guy and all!! they gave me tha same vibe. 

Saving the world from destruction. Main character just a normal girl except, has the power needed to save the world. 

Main heroes in both series falls down from Heaven/Tower whatever. Both girls seem to have some unique powers but strongly deny it. Both reeeeealy need some continuation. 

It's pretty similar.There is also a girl who wants to reach the sky and when i look at Yumemi from Munto I get the feeling that she's a clone of Misuzu . The stories are both complex and a little hard to understand and there is also a character ready to sacrifice himself for the sake of others. 

Both are about a boy and a girl from different places, that have to be united to save the world.  

The first arc of 5cm/s is similar to a sideplot of Munto in which a couple thirteen year olds decide it's time to be together for the rest of their lives.