Starting with the MZ series they broke away and made a machine with the Zilog Z80 in it (of NES fame, a well known architecture and a good choice at the time) continuing on through the X1 series.
Starting with the PC-5000 (I had a chance to buy a perfect Sharp PC-7000 portable but I didn't *kicks self*) it made PCs pretty close to U.S. The Sharp 圆8000 was by no means their first foray into the big world of computing.
The 圆8000 really doesn't bring to mind hentai, but since it was popular there would of course be some. The Hentai machine for the late 80s was the PC-98 based computer (as usual, those machines are most pointedly NOT IBM PS/2 compatible, though the early, pre-Windows Marty's vertical CD-ROM drive visible on the case is wicked cool). I've seen FM Towns Marty PCs for sale ($299 + S&H) THAT is THE hentai machine of the early 1990s. I know somebody who got a shitty, beat up 圆8000 ACE HD (hard drive model) for about half a grand, but that was a few years ago and I think he bought it from somebody inside the U.S. If you've got a ton of money, you can get one shipped from Japan or Hong Kong. Great to see that I got people thinking about this machine. Edit: Oh yeah, while we're on the subject, I managed to take a decent picture of that Akumajo Dracula 圆8000: