"Just one call, and I'll be there for you." From childhood games of hide-and-seek to silly squabbles that ended in tears. This VOCALOID track celebrates the unbreakable bond between the older brother, "P-fura," and his younger sister, "Pancake." Though their paths may lead them to different places, they remain "Happiness Birds," forever connected by an invisible thread. A song of love, growth, and the solemn promise to always be there for one another.