Some offices have stereotypical dynamics: the chauvinistic pig of a boss who never does any real work; the employees whose goal is to suck up to the boss; the ones whose lives seem perfect; and the individuals who have all the actual work pushed onto them. Retsuko the red panda is in the last group, as she stays late most nights to make up the work her coworkers are too lazy to do themselves. Her relief from the stress of her everyday life comes in the form of singing death metal at a local karaoke club. Night after night, Retsuko channels her grief into a microphone and considers the place to be her own personal sanctuary. But as she moves further away from her comfort zone and the ideas people have of her, she discovers that letting others into her world of death metal may not be such a bad thing. [Written by MAL Rewrite]

The anime adaptation of the four-panel manga "Ai Mai Mii". The story follows girls in a manga club—Ai, Mai, Mii, and Ponoka-senpai—who might be fighting evil invaders threatening Earth, facing off against rivals in tournaments, and dealing with other absurd situations when they are not drawing manga. (Source: ANN)

Aine Yuuki, who is a regular student at Star Harmony Academy's normal division, meets Mio Minato from the idol division, who invites her to join Aikatsu to fulfill Aine's goal to make friends. She also befriends Maika Chōno and Ema Hinata who are also idols. Aine and Mio form a pair to become best friends to become the bright "Diamond Friends". Karen Kamishiro and Mirai Asuku are categorized as "Diamond Friends" and are in the Diamond Class! (Source: Wikipedia)

The story takes place two years after Aikatsu Friends! with Aine Yuuki now in high school. One day she has an encounter with the mysterious idol Hibiki Tenshou who wears the shining Jeweling Dress.