Tenchi Muyou! in Love

The intergalactic criminal Kain escapes confinement and turns his hatred toward Earth, striking not at Tenchi Masaki directly but at Tenchi's mother, Achika, decades in the past. As old home-video footage begins changing and Tenchi himself starts fading from existence, Washu realizes that history is being rewritten.

Tenchi and his companions travel back to 1970, when Achika and Nobuyuki were still high-school students, and hide among their classmates while waiting for Kain's attack. Protecting Achika is their only way to preserve the present, but Kain's power over time forces the group into a battle where losing one young woman could erase Tenchi's entire future.