There were MAX books that were truly for adults and there were MAX books that basically told 616 stories but threw in a curse or a boob here or there.
The Eternal was definitely a MAX book. It wasn’t very good, but it was over the top.
It started back in caveman days and really plays up the idea of The Eternals as part of the movers of human history–and not always in a good way. We see them evolve humanity into deviants who can serve as slaves (and sometimes sex slaves), and battle with their Celestial forefathers. There are inconsistencies with Jack Kirby’s version of the early Eternals history, so I’m saying this is an alternate-Earth story–not canon.
It’s full of gore and tits. If you like that stuff, you might like this. But there’s not much of a story and it’s very “sacred” and self-important.
It was launched as a monthly series, but was shut down after six issues failed to catch on with readers.