Cruelty in the Natal Chart

Saturn in hard aspect to Pluto is supposed to show cruelty in the natal chart. Hard aspect would be the conjunction( in this case), the square and the opposition. As with all things in Astrology, degree matters. I wonder why this aspect denotes cruelty. I do know that Saturn makes obsessive what it touches. I have seen Saturn conjunct Eros  obsessed with sex. I have seen Saturn conjunct Echo  obsessed with finding one’s voice. In the same way, Saturn must make Pluto obsessed with expressing POWER. How best to express power than cruelty. I suppose cruelty is absolute power.  In any case, please share your experiences and we will discover more about this aspect, together.