This episode came pretty fast, huh? I was certainly caught off guard. We are starting sill: See, Aphrodite A was lost long ago, leaving the perpetually useless Sayaka without a robot. Sayaka couldn't stand being any more useless than she already was, so she asked the three goofball scientists to build her a new robot. She wants it built to look like her (yes, this is a carryover from the original Mazinger), so here's the Go Nagai logic: the scientists can't possibly build a robot that looks like Sayaka unless they have some nude pictures of her. And so it is that the episode begins with Kouji fighting off the three scientists as they attempt to strip Sayaka bare.
Of course, when the situation is explained to Kouji, it clicks with his Go Nagai logic, and he decides to kick these three assholes out of the room and take the pictures himself. Sayaka is quite pleased with this turn of events, but Shirou pops in and lets everybody know that the robot's already been built. Who built it then? Professor Yumi, I suppose? Or are the three scientists just sneaky bastards who were planning on Sayaka the robot after they got her nudes? The only thing we know for sure is that Venus A has a well-defined ass, which is an even weirder thing for a robot to have than boob missiles.
Kouji and Sayaka get some much-needed flirt time in before Tesshou Genda scolds them-- there are armies incoming, you kids! Do this love crap later! It goes without saying that Brocken's armies wreck the non-robot military, and that the "we won't have our asses kicked quite so fast this time!" Mazinger Corps get so served by Mechanical Beast Baron Ashura that they don't even bother showing it onscreen. Meanwhile, Boss Borot waits at the Photon Power Labs for its chance to shine. Ankokuji visits, and he's clearly up to something: the Kurogane gang speculate that he might have allied with Kenzo Kabuto.
Ashura's robot makes its real debut at the grave of Juuzou Kabuto. The Kabutos are trying to have a nice, early memorial service before Dr. Hell shows up, but you know what? Dr. Hell shows up anyway-- in hologram form. He even leaves some hologram flowers on the grave. And then the fiery wreckage of the Mazinger Corps appear, and then so does Ashura. Venus shows up, and she's a little useful here, but like the Mazinger Corps, her robot upgrade only means that she won't be beaten quite as quickly as she was in the past. Ashura and Dr. Hell offer a duel. Single combat. Whoever wins gets their way. You know, the usual cartoon bad guy trap.
Say, did you know that there's a giant Devilman statue in the Kurogane bath? Because there is. In the end, Shirou, Kouji, Boss and the lackeys talk over the offer. Kouji wants to stick to the plan, so he has to refuse Ashura. Of course, everybody else present-- yes, even the little boy-- replies with "what kind of man are you?" Boss even finds a little common ground with Ashura, as a rival determined to win and destined to lose. Everybody walks out of the bath in disgust, leaving Kouji to ponder how he wants to fight Ashura more than anybody. A bathing Sayaka has overheard the whole thing and jumps out to console Kouji, who promises not to accept the duel.
Of course, there are a lot of things a guy will say to a naked girl, and as Tesshou Genda so boldly declares, "A man! Kouji is a man!" As Kouji and Mazinger walk slowly, backs hunched over purposefully, towards an obvious trap, Kanjite Knight is reprised in the background. Imagawa knows it's the best, just like we do. I assume Imagawa also fast-forwards the ending credits every single episode, like I do.