扉の向こう (Tobira no Mukou)

Background
The song was first uploaded on November 18th 2010; making it Shigotoshite-P's first work using the vocaloid Nekomura Iroha. It's featured in the compilation THE VOCALOID PRODUCED BY YAMAHA as Iroha's track, and also was featured and remastered in Shigotoshite-P's album "SS Tobira no Mukou no Sono Saki e"

According to Shigotoshite-P's description on the song as commented from her mylist, in the "other side of the door" lies a "me" (in this case, Iroha) without you tomorrow.

Nevertheless, interpretations are open to its vague lyrics. (Also, as a note, the "gibberish" in here has no definite meaning whatsoever)