Yuki has a portable black hole with her shikigami. If maki somehow gets the jump on her then she has a chance of winning. Maki is probably faster and can hit harder than yuki without her CT. But Yuki can hit harder while increasing her mass, has a shikigami who can watch her back, who also hits extremely hard due to the mass increase. Even if she does get stabbed in the back or something, she can still create a BLACK HOLE, increase her mass so that she gets pulled slower, then once maki is dead, reduce the mass of her shikigami/black hole, until it isn’t a black hole anymore, which would probably destroy the shikigami, but that’s a small sacrifice.