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We have performed systematic studies of narrow Fe-K line (6.4 keV) fluxvariability and Ni-K line intensity for Seyfert galaxies, using {\em Suzaku}and {\em XMM-Newton} archival data. Significant Fe-K line variability ofseveral tens percents was detected for a pair of observations separated by1000--2000 days (Cen A, IC 4329 A, NGC 3516, and NGC 4151) and 158 days (NGC3516). These timescales are larger by a factor of 10--100 than the inner radiusof torus, consistent with the view that X-ray reflection by torus is a mainorigin of a narrow Fe-K line. Ni-K line was detected with $>2\sigma$ level forthe Circinus galaxy, Cen A, MRK 3, NGC 4388, and NGC 4151. A mean and varianceof Ni-K$\alpha$ to Fe-K$\alpha$ line intensity ratio are 0.066 and 0.026,respectively. Comparing this with the Monte-Carlo simulation of reflection, Nito Fe abundance ratio is 1.9$\pm$0.8 solar. We discuss the results andpossibility of Ni abundance enhancement.

Fe-K Line Time variability and Ni abundance of Distant Reflector in Seyfert Galaxies