Tiffany Reisz’s sinners series had a few good characters like this; Wesley was the best. Not looking for “alpha male, but secret virgin,” definitely want the nervous, innocent virgin, or at least very inexperienced. Cougar stories would be great, but the ones I’ve read tend to have (a) sexually assured younger love interests, or (b) serious love stories, neither of which are what I’m looking for.
Source: reddit.com/r/eroticliterature/comments/dn96q4/recommendations_booksstories_with_innocent_male