http://tvtropes.org/pmwiki/pmwiki.php/Recap/YuunaAndTheHauntedHotSpringsOkinawaSummerVacationArc
Chapter 28: Yuuna-san and the Other's Journey to the Southern Country
Kogarashi, Yuuna, Nonko, and Oboro are left alone at the inn for the summer due to Sagiri and Yaya returning to their families, Chitose going on a trip, and Chisaki taking in Koyuzu at her home. As a thank you for Kogarashi helping finish her manga again, Nonko takes everyone remaining on vacation to a beach villa she owns in Okinawa. The 4 of them enjoy their time at the beach with Kogarashi applying sunscreen to the girls only for Yuuna to send him flying off out of embarrassment. During flight, Kogarashi spots a female spirit hanging out on a cliff, which he learns from Nonko shortly after that said cliff is subject to an old folklore where a tragic love-story occurred. Said story being that a man died before he could meet with his loved one at the cliff, which the girl then committed suicide out of grief. Kogarashi and Yuuna head off to meet the female spirit at the cliff, which the spirit informs them that she's waiting on the day that she can cut the man she's waiting for to pieces.
Chapter 29: The Tragic Love Story and Kogarashi-kun
Wanting to see her man one last time, the female spirit introduces herself as Ami claiming that what she said about cutting someone was a joke, and asks for Kogarashi and Yuuna to retrieve her spirit boyfriend from a different cliff that they can see in the distance. The 2 of them head to the cliff with the male spirit on it, which he introduces himself as Yasuhisa, but he's been too nervous to actually go to Ami's location since he's worried of what she will think of him knowing that his death led to her dying as well. Kogarashi forces Yasuhisa to act by claiming that he's going to help Ami pass on to the afterlife, which causes Yasuhisa to follow Kogarashi back to Ami's cliff. Ami and Yasuhisa let out all the emotions they've been holding in all this time towards one another, which finally allows the two of them to pass on to the afterlife. Witnessing Ami and Yasuhisa's story gives Kogarashi the theory that earthbound spirits have trouble reliving the event that led to their deaths, which he asks Yuuna to tell him her story of the last time she was still alive since it's probably connected to what she truly regrets.
Chapter 30: Before Yuragi Inn's Yuuna-san
Back at the villa, Oboro questions Nonko who Yuuna really is, which Nonko answers that even she doesn't know other than what she knows about Yuuna's spirit form, but she theorizes that Yuuna was probably a strong psychic when she was alive. Meanwhile, Yuuna informs Kogarashi that she doesn't actually remember anything about her living self, and that the earliest she remembers was waking up as a spirit being taking care of by Chitose at Yuragi Inn. Despite that, Yuuna remains questioning why she would have regret when she's already made friends with Kogarashi and company. Upon returning to the villa, Kogarashi chats with Nonko about how Yuuna may become an evil spirit if she doesn't pass on to the afterlife. However, Nonko assures him that such a case won't happen since spirits that go evil tend to be the lonely ones, which is something that won't happen to Yuuna as long as her friends continue to stick with her. Overall, Kogarashi remains determined to always remain at Yuuna's side in order to make sure that she doesn't go evil.
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