So I adopted a cat from Athens in February this year. He had been a street cat and abused - was kicked in the face etc, needed his eye removed amongst other things. He's about a year old now. Given that he's not scared of people at all, and loves everyone. The issue is with my other cat, she's quite a shy and nervous cat, the total opposite of him. I started off keeping him in a separate room, and then slowly lifted the curtain so they could see each other, and also started feeding both of them on opposite sides of the door. Never had any issues there. I've tried to introduce them countless times, but it just turns into him stalking her, chasing her, jumping on her, pinning her to the floor, biting her, walking round her in circles and swiping at her etc. And obviously she doesn't like it and tries to run away and hide, starts to become really vocal and agitated/panicked. There have been times where they've come face and face, and she has been quite happy to walk up to him and sniff his nose etc. But then he just ruins it again by pouncing on her/chasing her/biting/hitting her. I no longer let him in my bedroom, as that's her safe space - where she eats, sleeps, litter tray. But for the past 4 months or so, I just have them mainly separate, when she's asleep, I have him roaming the house or free to roam where he wants as it were. And when she wakes up, I'll keep him downstairs, and then at night I put him in his room so she can go wherever she wants. It's becoming a bit of a chore having to police what areas they can be in. And I don't know how to get him to calm down around her.