Three soldiers ride MOSPEADAs through the rain in a desert. A man on a motorcycle gives chase, and they realize he’s the infamous Rainy Boy. He blocks their path and kills all of them with his gun and missiles. He then pulls out a knife and marks the kills as his 88th, 89th and 90th. Later, Stick and the others meet with soldiers who bury the dead men and explain that Rainy Boy is a killer who only attacks soldiers. Stick comments that they never would’ve met the soldiers if not for Rainy Boy, and Yellow is surprised that other survivors were also heading for Reflex Point. Stick asks if Rainy Boy is a human Inbit, and the soldier answers that he isn’t, adding that he only comes out on rainy days, hence the name. Jim thinks that they need to kill Rainy Boy, and the other soldiers agree to help. Elsewhere, Houquet and Ray drive off on their bikes to scout ahead, but Mint is annoyed at being left behind. She tells Aisha that she won’t forgive Ray and Houquet if the killer turns out to be a handsome guy. Ray and Houquet drive through the desert and come under attack from a Gamo and several Eagers. Houquet destroys one of the Eagers, but the Gamo chases after Ray. Houquet joins up with Ray again as the two are cornered behind a large rock. They spot Rainy Boy in the distance burning lots of HBT, and the Inbit retreat. Rainy Boy then falls off his bike and passes out. Later, Houquet removes a bullet from his arm and tells him he’s too reckless. She looks at his open shirt and notices that the right side of his body is entirely cybernetic. He tells her he can handle the rest, but she insists on wrapping up his arm, and he comments that most women run away when they see his cybernetic half. Ray appears with his gun drawn and asks Rainy Boy why the Inbit ran if they saw him. He asks if Rainy Boy is a human Inbit, and Rainy Boy asks what Ray will do if he is. Ray then shoots near to his head, and Rainy Boy draws his gun and shoots Ray’s out of his hand. Houquet jokes that if Rainy Boy were really an Inbit, Ray would be dead. When they’re alone, Rainy Boy asks Houquet why she’s going to Reflex Point when she’s not even a soldier. She answers that some of her friends are soldiers, and it’s hard to live alone. Rainy Boy tells her that his cybernetic arm squeaks on rainy days and that his outlaw blood excites the arm. Ray pulls up and tells Houquet they should go to the town everyone else is at. Rainy Boy asks Houquet why she didn’t ask about the Inbit, and she tells him it’s not her nature to pry. After he drives off, she realizes that she never asked his name. Houquet and Ray drive to town and find Yellow performing in a restaurant. Several soldiers walk into the bar, and one of them has a picture of Rainy Boy from the camera of one of his victims. Houquet and Ray are shocked to see that Rainy Boy is the man they met.
Houquet sits outside alone and wonders why the man she met had to be Rainy Boy. Aisha joins Houquet and asks if she’s going to tell Stick. Houquet asks if Aisha wants her to rely on Stick and if so what difference that would make. She says it’s not Stick’s business and that everyone has their own problems. She adds that she’s too cowardly to get involved with other people’s problems, but she also doesn’t like people prying into her affairs. It begins to rain, and Houquet flies into the desert in her Zeta Legioss, where she finds Rainy Boy. Elsewhere, the rest of the group and the soldiers engage the Inbit. Ray’s Iota Legioss is surrounded in the air by Eagers, and he wonders where Houquet has run off to. Rainy Boy asks Houquet what’s wrong, and she tells him she can’t leave the people who are going to be fighting him soon. He answers that no matter what she says, he can’t stop what he’s doing. Houquet then draws her gun, and Rainy Boy tells her to shoot his left side, but she can’t. They hear the sound of battle in the distance, and Rainy Boy says he can’t let the Inbit get more points. He explains that the Inbit took the entire right side of his body and cyberized it for experimentation, probably to learn about human evolution. The Inbit told him that they’d restore his body if he killed 100 soldiers. He shows her to marks carved into his cyborg arm and says that with 10 more kills he can go back to normal. Elsewhere, Stick and the others try to hold off the Inbit, who fall back when Rainy Boy appears. Rainy Boy counts 10 soldiers in the group and declares that he can stop killing after today. He kills two soldiers with missiles, and comes under fire from the rest. Rainy Boy kills all the other soldiers, leaving only Stick, Jim and Yellow. His motorcycle gets destroyed in the process, and the others see his damaged cyborg parts. A Gamo tries to attack Ray from behind, but Houquet flies in and destroys it. Together, they unleash a volley of missiles to destroy the remaining Eagers. Rainy Boy takes out everyone with punches from his cyborg fist and prepares to shoot Stick when Houquet lands nearby. She tells Rainy Boy that she can’t shoot him, but she can be shot in place of her friends. She stands in front of Stick and tells Rainy Boy that she needs friends and can’t ask people about themselves because she’s a coward. Rainy Boy tells her that she’s an idiot and puts down his gun. The damaged Gamo appears and prepares to fire, but Rainy Boy gets off a shot on it and is killed in the process. Only his hat is left behind, and Houquet begins to cry as it stops raining.
The group’s journey takes them so somewhere vaguely in the American Midwest, so they’re definitely closing in on their goal of Reflex Point. However, they and other soldiers are being blocked by a mass murdered known only as Rainy Boy. He has a half cyborg body that was given to him during an Inbit experiment. I wonder if the experiments on him led to the creation of Aisha, Battlar and Solzie. Houquet meets Rainy Boy and kind of falls for him, although I don’t see why other than that he’s a mysterious pretty boy. Well, he does have a motorcycle, and given that she used to be in a motorcycle gang, there is that aspect. She’s usually very private about her feelings, so it’s a change here to see her open herself up in front of everyone. She’s willing to sacrifice herself to save everyone, but in the end Rainy Boy is the one who ends up making the sacrifice.