Yes, you are correct.
There are currently no interaction hitboxes around her mouth during the Doggy Style scene, so selecting it will not trigger any interaction.
If you frequently encounter this issue, you may want to report it to the developer through the official Discord server.
When reporting a bug, it helps a lot if you include screenshots or a short video showing the issue.
You can post it in the #🐞bug-report channel so the developer and testers can review it more easily.