The Zero-Sum Original Anthology Series features themed oneshots from various mangaka that publish in Ichijinsha's Zero-Sum and Ward magazines. Volume 10 theme: Conflict and Secret Societies.1. Ranpo-sensei Laughs Like This by Takayama Shinobu2. Secret Mission by Saeki Yashiro3. Fang by Kawazoe Mariko & Nakamura Sachiko4. Black Swastika Army by Katagiri Ikumi5. Mushroom and Kappa - A Fierce Conflict of Honourable Men by Magami Guriko6. Boys’ Cavalry by Kayase Shiki7. Rindou by Asada Yasuka8. Hideout by Sekka9. Un Orso by Mizuhara Kenta10. Be Enthusiastic, Father! by Inui Miku11. A Promise by Seno Tatsune & Takamiya Aya12. Let’s Meet at the Secret Society by Kinoshita Sakura13. Will O' the Wisp by Kouzuki Leo14. The Village of the Secret Agreement by Ueda Shinshu15. At the End of an Endless Desire by Akai Higasa16. Demon King Time by Kanou Ruri17. Messenger of Justice ★ Moonlight Organisation by Usaki Hitomi

Rune believes that good children get spoiled except for her. She decides to run away from home. On the train she took, she encountered an odd stranger named Busujima... who keeps on insisting that she's an egg!