To date, there are seventeen volumes in the True Tenchi Muyo! GXP series of light novels. Volume 14 was written by Masaki Kajishima, and has yet to be published outside of the main readership in Japan.
Seina travels with Airi to register Acha with the GP immigration services. Meanwhile, Hiroshi reveals that Miki was in fact based off of Tsukiko, leading to Tsukiko becoming better acquainted with Miki and ultimately assuming the roles of motherhood.
D tells Seina some more about the events in Dual! and that many of the girls who surround him actually resemble the girls from Kazuki's life. This prompts Seina to ask Washu about this insight. She reveals that these groups tend to gravitate to Seina to correct for some probability bias, but it is unclear whether that bias is distinct to Seina or something from a long line of ancestors.
Airi finishes with some other tasks and catches up to Seina again, bringing Miki along to stay at the apartment. Over dinner, Seina brings Airi up to speed about the events in the previous volume, such as the discovery of a connection spanning billions of years between the crew of the Kamidake and the old Rara/Sonada protagonists from Dual!
The conversation settles on a chronicling of Zinv's exploits many epochs ago and how impactful that might be to the current research and development of the Royal Trees of Jurai. In addition to some new concepts about battle fatigue and the link masters have with their Trees, the group learns that Ryoko Hakubi has experienced similar dynamics piloting Ryo-Ohki. At that point the conversation halts, until Seto cryptically rebuffs further questions, expelling everyone from the room except Seina.
Seina bounces from several impromptu meetings with GP officials, including a private conversation with Seto. Airi meanwhile occupies the girls' time with some updates on her work and future activities. She mentions that while raising Kiyone and Minaho with Yosho became a priority spanning the Middle Ages and Enlightenment, in more recent memory, she has not had any marital or extramarital relations in the last 150 years.
Adding to her headache, she is ultimately responsible for arranging all of the girls' upcoming marriage with Seina, something Seto believes is bound to happen imminently.
Before long, it is the big day, and Seina stands ready to marry Kiriko, Amane, Ryoko, Neju and Fuku. But trouble ensues when some of the ladies-in-waiting (Secretly agents from the Renza Federation) pull a fast one and escape with Seina. Then Seina's kidnappers attest this escapade was a mutually agreed upon elopement, and to make matters worse, they string him up, threatening to molest him in plain view of the wedding party. Before any countermeasures can be thrown into the mix, the kidnappers whisk Seina aboard their prized Racepshi, gunning for Renzan controlled space.