It starts with A Dinosaur attack and Michiru Saotome just coming out of the bath... naked. We get a brief rundown of how Dinosaurs evolved into lizardmen and hid in the earth for 10 million years to escape cosmic rays(there's actual conspiracy theories about this with the queen and hilery being them). They fight the Mechasaur and slag it as Sirene watches. Emperor Gore says the Dinosaur Empires machine land floating in magma is gonna collapse soon and they gotta wipe out humans before that happens. Then the Demons contact them and say they both had been competing for Earth in ancient times, but Demons hid in ice and Dinosaurs hid in lava. So they should team up and the demons will beat Getter Robo somehow. Akira Fudo and Miki Makimura are traveling w/o parents(well,... Miki is) and visit Saotome Labs. The Getter team showers as we see Muashi's big butt in its own panel, the they wanna get beer despite being highschoolers. Michiru introduces the Getter team to her childhood friend Miki Makimua but they are lustier than usual as they were written by Go Nagai and go after Miki (is this going to be Violence Jack Evil Town??) Akira tells em off for scaring her and they fight. After revealing Akira's past, Michiru reveals Miki and Akira am her the guest. A storm happens and the Getter Team make Akira stay with them even though hes Miki's bodyguard(and what a body to guard!!). The chapter ends with Miki and Michiru taking a bath in a hot spring as Sirene is above em.
It starts with Silene saying how shes gonna make this place f'd and Akira telling the Getter Team Miki is targeted by demons. Miki and Michiru playfully mo lest each other by feeling each others breasts and Michiru reaches a bit lower but the demons attack and a Gelmer looking guy called Gelgar starts molesting them with water. The Getter guys take on daemons and do pretty well against em despite at 1st thinking they were guys in costumes who can pass through walls. Akira attacks Gelgar and saves Miki but Michiru is captured and Akira transforms. The security saved the g boys and they go to the Getter Robo. Gelgar takes a while to decide if he wants to rape, eat or kill Michiru and by the time he decides to do all of the above at the same time, Akira busts him. Getter robo busts demons and sees Devilman over Michiru so it takes him on thinking hes a demon. the chapter ends with Sirene holding Michiru (who has balloon b00bs) saying shes gonna slag the winner between Devilman VS GETTER ROBO.
Devilman fights Getter robo for a bit b4 turning on Sirene. Akira saves her and transforms to human w/ bat wings (h-llstinger from Voltage Fighter Gowcaizer??). Akira puts the naked chicks to bed and feels its a same to cover their hot nude bods with a blanket. Akira explains that no one human knows his secret but as he fused with Amon, they see him as a traitor and Sirene wants to kill Miki. Sirene licks her wounds from the battle and the Dinosaur Empire sends a buncha Mechasaurus to stop Getter Robo. Getter wastes 3 elite Mechasaurs so Gore decides to work with the demons. The 3 elite Mechasaurus's fuse with demons and attack Getter Robo. the chapter ends with Akira transforming.
Getter Robo fights the Demon Mechasaurus's but they are mushy and squish instead of cut from GETTER TOMOHAWK!! So Akira comes in and blasts em with DEVIL BEAM!! In the Lab Dr. Saotome sez they are losing so he sez he made the Getter Queen, a robot with a cockpit that only a woman or chold can use as its too small(what about a Midget??) Also it needs two pilots so Miki and Michiru pilot it. Getter Robo is performing poorly against the monsters but is saved by Getter queen and they team up to beat em. But Sirene has combined with a Mechasaurus demon and is heading for the lab. So Devilman and Getter Robo combine into Devil Getter and it looks sick!! The Lab puts up a Magnetic Barrier but Devil Getter f's up Mechasaurus Demon Sirene's monsters with a big a55 axe!! Sirene blasts through her own guy to nail Devil Getter but he gets up and nukes her with a Getter beam!! but it melts her and she turns into Mecha Demon Sirene!! as Sirene and the Mecha parts survive and her strength survived (like in Contra when the boss has another form). She blasts em but they undo their fusion and Devilman grabs Sirene's breasts. He tells her that she should be sexy and that her fused form wasn't. Pulling her out of the Mechasaurus fusion, Getter Robo beats the machine she was fused to and Sirene thanks him for making her remember Amon. She kicks him away and sez she'll kill him next time. Later they say bye and Akira sez he'd like to meet Kotetsu Jeeg or Iron Muscle. Miki suggests Aztekaiser or Battle Hawk but Akira sez it should be Kekko Kamen as they drive off on Akira's Motorcycle.