Mechanic suggestion: Hypnosis
I'm not suggesting the game changes track and becomes a hypnosis focused game but use hypnosis as an excuse for a game mechanic that causes one or more modifiers to a session.
Each modifier positively affects one thing and negatively affects another, something like the following:
"You are a doggy !"
Able to move faster while crawling but detected faster while standing.
"You are brave !" slower detection but reduced score.
"You are hot !" Move much slower wearing any non revealing / lewd clothing but move faster while wearing only revealing / lewd clothing.
This could be introduced by another NPC - one who wants to support / take advantage of the main character - and completing a hypnosis challenge unlocks the ability to use it elsewhere.
Something like the quake arena mutators if you are familiar with that.
Jewelery: Cute Collar
A pink collar with a gold heart name tag.
Can be worn on the characters wrists, ankles and neck - wearing on the character neck requires a higher level of perversion, more so if its the only thing voluntarily worn - no special functions.
General suggestion: The option to choose the color/s of clothing.