As Mahiro tries to understand his recent dream, where he and Nyaruko are wedded, Tamao soon invites everyone to check out a new attraction that has opened in town. But after everyone traverses and goes about the rest of the day, Nyaruko and Mahiro find themselves trapped by an unknown enemy that has replaced their real selves with alien impostors and forces them to try and escape while a deadly space-nano virus has infiltrated Nyaruko's body, taking away her powers and slowly saps away her memories. Their friends soon realize the switch and defeat the fakes before going back to find the real ones. Still trapped, Nyaruko's personality soon starts to fade as Mahiro risks his own safety to protect her. Having reached the end of the challenge but have run out of time, Mahiro begs the mysterious voice to return Nyaruko to remember in exchange for agreeing to aide him. However, Nyaruko, with what little memories she has left, persuades Mahiro to stay himself as she admits that she will never forget how much she truly loves him. This brings Mahiro to tears as he confirms her feelings with a kiss. Soon after, they are ejected from their prison and back into the real world with Nyaruko's original personality intact but with their memories of that day erased. However, a letter found later in Mahiro's school bag reveals it was Mahiro sharing a kiss with her that cured Nyaruko's condition, written as "sharing bodily fluids". This stuns and shocks everyone else around him, as the others were nearby when he read the letter, before Nyaruko and Mahiro end the special with one last kiss in front of them.