I've met about 20 of them and each of them has little to none redeemable qualities, here are the most notorious examples I can think of:
>Ex gf's dad
Who married her mother just to father a child and had an affair with a 25 year old who he pampers and treats like a son while he barely acknowledges his daughters excistence. He finds a way for her to love him unconditionally by indirectly making her focus on the negative aspects of her relationship with her mother, downplaying the fact that he himself was responsible for the woman's misery.
He pavlovs the shit out of the poor girl into idolizing him even after being told stories by her uncles about how her father used to kick strays as hard as he could because he didn't like them.
>Personal psychologist
He tried to get me to squeeze like a lemon and vent all of my frustrations and anger to him throught numerous sessions, when I tried to leave, he got agressive and told me shit like that I was escaping the root of my problems and shit like that when I was already fine. Years later he confessed he had a crush on me and didn't want to let me go, hoping we could have something together.