The August issue of Kadokawa's Monthly Dragon Age magazine revealed on Monday that Misaki Mori will launch the Trinity Seven: Seven Days manga spinoff of Kenji Saito and Akinari Nao's Trinity Seven manga in the magazine's next issue on August 9. The magazine describes the spinoff as a "sometimes slapstick romantic comedy."

The July issue of the magazine revealed on June 9 that Saito and Nao's manga would have a "super important announcement" in the next issue on July 9. The manga also has a color opening page in the most recent issue and features on the front cover.

Mori previously contributed a short manga to Trinity Seven Comic Anthology in January 2016.

Mori is currently serializing the Arifureta Nichijou de Sekaisaikyou manga spinoff of Ryo Shirakome's Arifureta - From Commonplace to World's Strongest light novel series. The manga launched in Overlap's Comic Gardo website in July 2017. Overlap published the manga's first compiled book volume on April 25.

Yen Press is publishing Saito and Nao's original manga in English. The company published the manga's 13th compiled book volume on May 22, and it describes the story:

Arata Kasuga transfers to the Royal Biblia Academy to solve the mystery of the destruction that is ravaging the world and that - more importantly - has stolen his cousin Hijiri from him. It's a tough road that lies ahead of Arata, but nothing's impossible when you have seven beautiful girls - each a master of her own magical art - at your side!

Saito and Nao launched the original manga in Monthly Dragon Age magazine in 2011. Kadokawa published the manga's 19th compiled book volume on July 9. The manga has more than 3 million copies in print. The manga has inspired spinoff manga including Trinity Seven: Liese Chronicle, which ended on June 9, and Trinity Seven: Levi Ninden.

The manga inspired a 12-episode television anime series that premiered in October 2014, and Crunchyroll streamed the anime as it aired in Japan. Sentai Filmworks released the series with an English dub on Blu-ray Disc and DVD in August 2016.

Crunchyroll also began streaming the Trinity Seven: Eternal Library & Alchemic Girl film in March 2017. The film opened in Japan in February 2017. The manga is inspiring a second anime film.

Sources: Monthly Dragon Age August issue, Comic Natalie