I wish I could find the post: there was a guy on Tumblr who said he did daddy roleplay shit with his girlfriend, until one day he was in the supermarket and overheard a little girl begging her mum to buy her a toy, and he got hard. He was horrified with himself and realised he'd been training his dick like Pavlov's dogs to be aroused by childish things and a childish voice, even though it was all faked by a grown adult woman with him. They stopped doing it immediately and apparently he's been normal and healthy since, but it freaked him out, and it shows how it can escalate if they don't stop.