It is understandable that she feels uneasy but... recording? Also understandable that he is angry at her for that... No one is wrong here... So as they make up, give us some ecchi chap next time :3
They sleep in the same bed and DON'T have sex but worry people are going to think she is smashing a minor? Wait ... what? Just from the fact that you spend the night in the same bed, someone could make a claim that you are smashing. Then how do you prove that you are NOT smashing? I guess you have to use your V-Card-is-intact get-out-of-jail-free token.
They are also hiding this from who ... exactly? Now that the new girl knows they have to worry about her throwing monkey wrenches in THAT plan. Should have smashed while you had the chance ... LOL. At least then he wouldn't be drooling over Miss Grab-em-by-the-dick over there.
My aunt is 9 years older than my uncle and and they didn't give a fuck about the age difference and they are relatively young so... It's not something of other world.