Pretense of Spring (Episode 15)

Pretense of Spring is the fifteenth episode of the anime series.

Synopsis
While traveling through the mountains, Ginko is given shelter, meeting a girl and her little brother while he is there. He later learns that every winter, the boy will go missing until he finally returns in spring.

Plot
On a snowy night, Ginko sees shelter in a house. There he meets Suzu and Miharu. On the next day, before leaving, he sees that Miharu can see Mushi and Suzu asks him for more information about them. She tells Ginko that three years ago, her brother went missing during the winter and they couldn't find him, but he returned in the spring. After that he started to see strange things. Then in the winter, when their winter food is about to run out, he disappears and returns collapsed on the next day with some green food and stays unconscious until spring. Ginko guesses that Harumagai are the cause, a false spring effect. He explains that there is a Mushi called Usobuki that looks like tree blossoms and its scent makes hibernating animals and plants active and then sucks out the life energy of those animals and the animals fall asleep until spring. Suzu asks Ginko to stay, but he explains he can't stay for long, but can teach Miharu on which Mushi are dangerous and which are not.

He starts teaching Miharu, but he is easily distracted by different Mushi. Ginko wants to know where Miharu found the greens, but Miharu doesn't want to say. Some days later, while Suzu heads to the village, Ginko realizes Miharu had wandered off and goes to look for him. He ends up finding him collapsed and with a small bag, which he opens and sees greens and Harumagai butterfly Mushi leaving. He takes him to his house, but as he can't stay any longer, due to Mushi starting to gather around him, he leaves and promises to return after some time.

Ginko returns to Suzu next year to find that Miharu haven't awaken during the spring. He decides to go look for the place Miharu went and find what is missing that usually awakens him. Seeing a butterfly and following a scent, he manages to find a small area full of green life. While trying to find which is the Usobuki, it becomes chilly and animals starts dropping unconscious. He starts to get sleepy too, but notices that only specific butterflies are not affected and manages to capture one. Suzu later finds him and brings him back to her house and accidentally finds and releases the butterfly in the house.

When spring came, Ginko and Miharu both awakens. Ginko realized that butterfly turns into flower-like object that releases certain smell and awakens them. He realizes that Miharu uses the Usobuki's emergency signal as a signal for the Harumagai and Miharu explains he would have awaken if he didn't release the butterfly as it would have turned into a flower and awaken him. But Ginko tells him, he should have told him that. Miharu states that he likes the butterflies the most and wanted to keep them a secret. As he realizes they are not bad, just trying to survive, Ginko confirms, they aren't friend but unusual neighbors, and there is nothing wrong to like them. Before leaving, he promises he will return again, just not in winter.