Richard Robinson wrote:
1: As I understand it, Black Magic doesn't depend on Mazoku for power.
Rather, it and the Mazoku depend on the same source of power, so-called
"negative" emotions.
Depends on the spell. Lower-level stuff, like, say, a Fireball, only
needs the "negative" emotions. But a Dragon Slave calls upon Shabrinago;
if Shabrinago's not there, you can't cast it. Similarly, the Giga Slave,
and, if I remember correctly, the Ragna Blade, call on the Lord of
Nightmares.
Since Ranma's apparently not going to be trying a Dragon Slave, the lack
of the Mazoku in his world shouldn't be a problem.
2: Don't the Mazoku have a world of their own anyway? Most demons do.
They do appear to live in some dimension apart from the world of men.
The exact nature of it is, as far as I know, unknown. Since Mazoku are
unknown in Ranma's world but appear frequently in Slayers, it is not
unreasonable to assume that wherever the Mazoku live has easy access to
Lina's world, but not to Ranma's.
Chris Mattern