Episode 0, consisting of two subepisodes: "Sekirei Shindan" (鶺鴒診断) and "Sekirei Yoka" (鶺鴒余暇), of Sekirei: Pure Engagement included on the first DVD/BD volume.

Set 10 years after Mahou Shoujo Lyrical Nanoha A's, Nanoha, Fate, Hayate and the rest of the crew are now working full time in the Time-Space Administration Bureau. Nanoha is a combat instructor, Fate is a special investigator, and Hayate is a commanding officer. They must unite once again to save the dimensions. Introducing new characters as well: Subaru, Teana, Caro and Erio. Stand by. Ready. Set up!

"In a shared room with my co-worker at the hotel?! Although I was warned not to do anything stupid, my eyes would inadvertently turn to her legs wrapped in pantyhose..." Unbeknownst to him however, Douki-chan secretly has feelings for him. As Douki-chan struggles to confess her feelings, her rivals, both the kouhai and senpai, continue to vie for his affection. realistically depicts the texture of clothes, cute expressions, and exciting situations with plenty of temptation, featuring a great deal of satisfying highlights. (Source: MAL News)

Even after spending a considerable amount of time with Takagi, Nishikata is still struggling to find a perfect plan to defeat the expert teaser. A battle of wits, a contest of physical prowess, a test of courage—any strategy he employs to expose her weaknesses is to no avail. On the contrary, Nishikata's pitiful attempts only reveal more of his own flaws, which Takagi takes advantage of to become increasingly daring in her teasing attempts. To make things worse for Nishikata, rumors about him and Takagi may have spread in class due to the frequent interactions between them. However, the optimistic Nishikata believes that wisdom comes with age and that as the days go by, his experience with her constant teasing will eventually bear fruit, leading him to the awaited moment of victory. Thus, Nishikata continues to strive for the seemingly impossible—to outsmart Takagi and make her blush with embarrassment. [Written by MAL Rewrite]