Note that this is not a Sega Master System. It's a Master System Girl. You know. Because it's pink. And has a girl on the front. And pastel buttons.
It was released in the mid-90s as a variant of the Master System Compact, a licensed version of Sega's classic console that was manufactured by Brazilian company Tec Toy. What made the MSC cool was that it was a wireless console, able to transmit its audio and video signals via RF (hence the giant antenna on top of the unit, which also doubled as the controller).
The Master System Girl was identical to the regular Master System Compact except for the colour scheme and slightly mad female mascot, and while both are hot property for serious collectors, who could overlook the pink one? I mean, it's a pink video game console. Outside of Japanese special editions, that's something you don't exactly see every day/year/decade.