More suggestions:
Naked and afraid scenario.
Functions similarity to the 'lost keys' and 'lost clothing' in so far as the character has lost both and needs to find them however its more of a challenge scenario.
Key changes:
Player character starts at a random location (normally accessible on foot) in the game world and NPC's a forced to spawn a minimum distance from the spawn location.
Player character starts out naked and locked out.
The detection bar fills up faster - +20% on easy, +40% on normal, +60% on hard, +80% on extreme (see below) - chalk this one up to someone reporting something before the scenario has begun and the character already knowing about it.
The keys item (required to complete the scenario) can be picked up if spotted manually but will be highlighted after a random piece of clothing is worn from the selection taken into the scenario.
Finding the clothing is optional to complete the scenario but may make it easier to finish successfully.
Could also work as a test for a lying down pose, standing up animation & scenario specific mechanic changes.
Extreme difficulty:
The embarrassment bar fulls up 50% faster and does not naturally decay however masturbating reduces it with an additional bonus for an orgasm.
Probably should have some additional bonuses for completing something on extreme difficulty - faster exp gain / faster unlocks ... something like that.