Kenzen Robo Daimidaler, Ore, Twintail ni Narimasu. Recommendations
Both have fetish as their main theme, and both have the same bad guys whom were much enjoyable than the protagonist. But KRD was more of ecchi while OTN was more about gender bender.
the enemies and good guys are both really silly and have a ridiculous reason for fighting, but it is still very funny
In my opinion:
Both where based on a very simple premise, that would make one's head scratch. Both also has the same MC who rather have some very obnoxious fetish and it also includes some harem romance, sci-fi and ecchi genre. Also, both animes have antagonists who were seemly a bunch of nice guys. But, the focus of each anime diffres since one anime was all about that "Hi-ERO" thingy, while in the other anime is more into that twin tails thing.
Just go and watch it and do scratch your heads if you do feel like scratching it
What the two have in common:
Both have the same theme based on a very simplistic random fetish plot.
Both also have the same over the top monologue, that is just a bit too much for something so simple.
Both have the same kind of antagonist versus protagonist kind of thing where the antagonist where more lovable than the protagonist.
They both have the same plot where fetish was the main theme, but, one was more about gender bender while the other was more about the female MC who has the unlucky role of having to endure the male MC's sexual advances.