Oh! Did you try clicking the circle? That starts the interaction. c: Once you have the snack at least of course. I just tried on a fresh install on a totally new PC. Although he showed up before I met woof, he wouldn't interact with me until after I had found the snack and given it to him (which you find in the machine next to where you meet woof). Once given the snack, the circle appeared, and clicking in the circle started the lewd. Not sure if it matters, but I had also already gone around and cleaned up all the boxes.
The circle is definitely confusing when you're used to using `S` to interact with anything (like giving him the snack). Usually, it's only when you're cumming that you click a circle, lol. cX