Yakusoku no Tobira (約束の扉)

"約束の扉" (Yakusoku no Tobira) is Shigotoshite-P's first singles to be released on KarenT, with the previous album being SS -Tobira no Mokou no sono saki he-. It's featured in KarenT's "Meiko's 8th Anniversary Festival" as one of the tracks released for the day.

It consist of one track "Yakusoku no Tobira" based on the song of the same name originally uploaded for Meiko's birthday 2012. The singles is purchasable from iTunes store and it's KarenT's page can be seen here.