It's a Genesis,
It's a Sega CD,
It's a Portable CD Player.
Friend of mine in college had one of these, still the coolest-looking game console I've ever seen.
Apparently ( Sega CDX/Multi-Mega | Retro Consoles Wiki | Fandom ) Sega didn’t make many of 'em, like only 5,000 were released in North America (elsewhere in the world they went by the name “Multi-Mega”).