Animal behaviorists: could the street cat I am trying to adopt actually rape my 14-year-old spayed female Jilly-cat?

He is a much bigger cat than she is—I am guessing he may be about 7 or 8, old enough to have known Jacky [and I believe Jacky chased him away a few times] and he seems to be fully equipped. See the series of photos I have posted on flicr in the set The Courtship of Tom Tigger

He began coming around about 3 months ago. He and a rival fought in front of my garden for a few years before that after Jacky died. My guess was that they were divvying up Jacky’s turf. But a neighbor had noted that the rival cat [who had a family] seemed to be no longer around.

He started wailing outside like a housecat who has been accidentally shut out of his home. He sounded so mournful and needy. After only seeing him flee when I came out I finally coaxed him to stop one night. Oddly, what he was interested in was Jilly. He would coo and cajole at her window and when she came out would wriggle and make all kinds of soft encouraging noises. I let myself almost believe he was my very-much missed Jacky-cat returned in another form because his love for me and Jilly was stronger than death. Jilly has missed him terribly too-they were inseparable [brother and sister—yin and yang—even got it on once because a blizzard delayed their vet appointment]. I started feeding him and watching to see how Jilly responded to him.

He comes around regularly and I feed him outside. He has started coming in sometimes but ne doesn’t stay. Sometimes he pursues her so aggressively that I tell him to leave. She seems somewhat intrigued but also defensive, mostly sits in a closed posture and stares back at him while he lies all sprawled out looking at her and making coaxing noises, but will sometimes actively pursuing her. However, she has walked up to him a few times and touched noses.And she also has gone out in the yard by herself apparently looking for him and has spent some time in close proximity to him. Yet sometimes she seems relieved to come inside and have me close the door to the bedroom in case he comes in through the cat door in the living room.

I have been hoping to find a new companion for her that she would accept and who would give her happiness, and I would like to help him if he is without a home. But not if inviting him to stay will make her anxious and not comfortable in her own home.

I have put notices up and no neighbor has claimed him. He is a much bigger cat than she is—I am guessing he may be about 7 or 8, old enough to have known Jacky [and I believed Jacky chased him away a few times] and seems to be fully equipped.

If he became tame enough to really adopt and bring in for vet care, would neutering at his age traumatize him and make him run away?

Sending a few pictures. Any animal behavior advice?

Thanks for any advice.