Hell's Hot Springs: Alien Girls and Colorful Exposed Bodies.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. As they travel, they find Tokugawa's hidden treasure and the entrance to Atlantis, which Lala nonchalantly passes by due to there being no hot springs nearby. They eventually come across what is known as the Seven Colored Hot Springs due to the water appearing as seven different colors. All the girls enjoy using the big and spacious springs, while Saruyama and Rito are stuck using a very small and cramped one. Saruyama decides to get out of the small spring and mess with the girls in the other hot springs. Rito soon follows, and sees Saruyama chasing after Risa and Mio, which Rito then tells him to stop. They come across Ryouko and Yami, who then punches them both with her hair stating that she hates ecchi people. Lala then tells Haruna she needs to leave the spring to try to find a hot spring she can bring back to Rito's house. Rito then finds Haruna and they try to start a conversation which is interrupted by Lala who tells them that they need to leave quickly because she accidentally hit an underground volcano. They come across a civilization of moles who seek to rule the Earth's surface, but the moles are then killed by the flowing magma, and everyone returns safely to the surface.