The series connecting the monthly theme songs of 315 Production's flagship program "Passion Challenge We are 315!" across 16 units is released! The 10th installment is Mofumofuen! In addition to a new unit song, it also contains each idol's solo ver.! As a bonus, a flyer with a serial code for unlocking a story is enclosed, allowing you to view a CD-bonus story within the "315 PASSION CONTENTS" of the Idolmaster Portal SideM brand page. Newly drawn illustration jacket.