Lala is seen watching a commercial on TV about the Tsumata Misami Hot Springs. She then tells Rito that she wants her own hot spring. Rito finds Lala attempting to build something in their yard. Lala then asks Rito to go get her a drink, so Rito heads to the store where he is suddenly attacked by Yami as a test. Rito tells her that Lala is back at home building something; after hearing this, Yami leaves. When Rito returns, he finds that Lala constructed a large drill machine which she intends to use to dig underground and hopefully find a hot spring. Mio, Risa, Ryouko, Yami, Haruna, and Saruyama are all invited to join Rito and Lala dig underground...