[Arczyx]

Originally Posted by Mentatsumi

There is though.

Spoiler for Drama CD and Refrain spoilers:

In the Drama CD "Bokura no Asa" Kyousuke affirms the fact that they are in the real world, and not a more stable world that Riki would have made.. And I believe that Drama CD is canon

There isn't a proof the Kyousuke who said that is not a product of Riki's dream though... (more like, there is no proof that our life is not a dream either, like matrix or inception)

...so the ending is not that happy after all...