I have 2 girls. Historically I've always had 1 cat, but 9 years ago I wanted to get a companion for Chynna because I was starting a position at the hospital that was 12 hour shifts. I felt it was too long to leave my girl home alone. However, her and Abby never became friends. I think Chynna would have preferred to be just left by herself for that length of time. They just tolerate one another. I think now Chynna tries to play sometimes but Abby is afraid of Chynna and growls and runs away.
Though the other day Abby was on the office chair and Chynna was sitting beside it. Abby would lick her paw, reach over the edge of the chair and smack Chynna on the top of the head and pull her paw back quickly and crouch back from the edge leaving Chynna looking around to see what hit her on the head