Wife knows and is not interested. Is looking for a keyholder elsewhere cheating?

Married nineteen years and it is a good marriage, I want to say that first. I have raised chastity twice, once badly and once properly, and she was kind about it both times and then never brought it up again. She is not disgusted. She is just not interested, the way I am not interested in her book club.

So the thought that keeps circling back is a keyholder who is not her. No meeting, no photos, nobody’s hands anywhere. Someone holding the key and setting a few rules while I get on with my life. Nothing romantic about it in my head.

But every time I get close to actually looking I stop, because I genuinely cannot tell whether what I am describing is a hobby or an affair with extra steps. Has anyone here done this with a partner who knows and does not take part? Where did it land for you?