Summer Day:Courtship Behavior.Shu and Inori is requested by Gai to bring Souta Tamadate, Hare Menjou and Kanon Kusama, classmates of the motion picture research club, to visit a beach resort at Oshima, though in a guise as a mission in which will require drawing out Souta's Void. After having some fun on the beach with the others, Shu pays a visit to the grave of his late father, Kurosu Ouma, the leading expert on the Apocalypse Virus before his untimely death amid the Lost Christmas incident. Gai explains to Shu that the mission is to break into a covert GHQ base disguised as a shrine, but Shu has to make use of Souta having feelings for Inori in order to draw out his Void. Later that night at a sidewalk, as Souta attempts to confess his love to Inori, Shu rushes in and draws out Souta's Void, embarrassing himself in front of the Funeral Parlor members hidden around the area. As Shu, Inori and Gai enter the vault of the base using Souta's Void, in the form of a camera that unlocks anything, they discover that the item they were looking for has gone missing. Keido, who previous infiltrated the vault using Kurosu's access card, stands before Kurosu's grave holding the item, a canister containing a meteorite which was the cause of the Apocalypse Virus. The next morning, Shu and Souta make amends to their friendship due to their inability of understanding each other. Finally, as everyone leaves Oshima, Inori explains to Shu how people's Voids change based on his relationship with them.