Is this behaviour inappropriate?

An elderly relative I care for has recently taken to putting his hand in his shirt and stroking his nipple all the time whenever I am with him which makes me feel quite uncomfortable. I asked if his skin was irritating him and he said no. I don’t know if I am over reacting to nothing maybe its a self soothing behaviour or something. I wondered if anyone else had experienced this?

Should have said he is in his 90s and early stage dementia.

If you feel uncomfortable I suggest there is something wrong. Go with you gut.

You do not say if there is any mental health issues.