君のいない場所で (Kimi no Inai Basho de)

Background
This song was uploaded on November 25th, 2008, and has reached over 65,000 views. It is Kea-P's most notable work, and is popular in the western fandommore than the eastern (the original reprint had around 400,000 views before it was taken down).

The song tells a story of two children who are sperated by a mirror, singing to each other in hopes that their voice will reach the other. In the end, the mirror cracks, and the two are overjoyed.