It's hard to understand exactly when and how otaku culture came to be. If the term was coined in the very early 80s as a "vulgarisation" of the respectful お宅 pronoun, that makes us believe that there were earlier signs of the development of that culture, with people who do not get along with the "group" and prefer staying home reading books and other "non-active" interest being referred to as such. They were probably one of the branches of the youth that was breaking away from conventional society and were in search of a further sense of individualism and self-fulfillment.
They enjoyed stories about science-fiction, big robots, fantasy settings, cute girls being sexy, rebellious characters, and so forth. And with the technological boom of the 70s and 80s, this lead to diversification in the themes and stories. One of those, in particular, is sex. through 2 things in particular:

• the PC98, which would give rise to the concept of eroge, considering that men made up the majority of users of that technology,
• and the OVA anime format, which could afford to be risky and less conventional

Dream Hunter Rem is exactly that. In fact, I'd say it's pretty representative of the sinful amateur works coming from young minds with a cool concept and who try to make it come to life regardless of their ability to do so. This work was originally a 20 min hentai OVA which was turned into a 3-episode OVA after gathering what seems to have been an unexpected popularity at the time. This is why the first episode is so different compared to the others: while episode 2 and 3 are dedicated to 1 story each, episode 1 uses the contents of the original pornographic OVA, now censored and even partly rewritten, while the second half is dedicated to another original story.

However, that particular aspect is not really a problem in itself since I actually have a lot more complaints about episode 2 and 3 than with episode 1 itself. In fact, while the latter is merely an interesting, dark take of the Mahou Shoujo genre with very straightforward plots and incredibly basic tropes and ideas, the former are more "fleshed out" stories featuring more characters and even twists. However, writing-wise, those episodes fail on so many aspects it actually hurts just remembering those. Dream Hunter Rem has no nuance, no subtlety, and a lot of aspects will break your suspension of disbelief, if not make you outright laugh because of how stupid they are.

There's a clear lack of understanding of how plot progression works, and certain scenes even come out of absolutely nowhere, show something irrelevant and then are never mentioned ever again, with no impact on the story whatsoever. Certain plot points are set up and then immediately dismissed or even subsequently made irrelevant, characters act randomly or even extremely edgy in an absurd way (episode 2 is extremely guilty of that) and then everything is forgotten minutes later. And even thematically, despite the anime actually doing a fine job setting up the story and atmosphere of each episode, it somehow manages to screw up something, like the random mecha in episode 2 that made zero sense. By the time episode 3 was rolling out its awful "twists", I was already missing the simplicity and fun of the 1st episode.

Visually, Rem doesn't look bad though and even displays some rather clean animation at times, giving us some fight scenes that even go beyond "serviceable" and border on "ambitious". It also has the "advantage" of displaying some pure 80s vintage, albeit missing too much shading to be considered "great" visually. There's also a clear aspect of weightlessness at times, but that is to be expected considering how daring some camera angles are. This OVA also wears its edginess on its sleeve, offering some gratuitous aspects of gore that certainly help make this work feel a bit more special as you wouldn't be able to see that kind of realistic gore much these days beyond works such as Edgerunners.