This question is now moot, because the cat died several years ago at an advanced age, but I have always been curious as to whether it would have been OK or horribly rude or somewhere in between.
Years ago, I attended a conference in Japan, and a young Japanese professor (clearly destined for a great future and who is now well known in his field) was very attentive to the people from the US who were attending the conference, and greatly enhanced our enjoyment of the conference and Japan.
A year later, my husband and I adopted two rescue kittens, and after a weekend of cudgeling our brains for names, decided to name the male after the professor, whose last name was Kit-----, because we could then call the male Kiti for short. We named the female Lady Murasaki, Saki for short.
If the professor had been in the US, I could have easily found a mutual close acquaintance to sound out the professor's likely reaction to the question, and, if positive, asked in a way that put no obligation on him to say yes. But I didn't have mutual acquaintances in Japan, I didn't want to risk a misunderstanding, and at that time I was senior to him. I did the right thing in not asking; that's not the question.
The question is: would it have been intrinsically offensive to ask a Japanese to name a cat after him? Or would it just depend on how much he liked cats?
I am hoping for an answer from someone familiar with Japanese culture. I know that there is a cat, the Japanese Bobtail, that is very popular in Japan, but I don't know if Japanese culture has any position on naming a cat after a person. As I've already said, it may depend simply on how a particular person feels about cats.