I understand that your roommates are not eager to have you walk around naked. But what about forgetting to lock the door while showering? After that, you could take your time drying off and shaving while still in the nude.
Also, have you checked if there are any art classes/courses in your area? You could apply to be a nude model. You might end up getting paid while enjoying your kink.
Or find a photo studio in your neighborhood and have a nude photo taken of you. Just tell them it's for your girlfriend. Those pictures will not be explicit, but you will spend some time without clothes in front of a stranger.
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I just started writing some erotica...
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Disclaimer: I'm always happy to give tasks to willing players within their likes and limits or - if it's meant as a punishment - dislikes and soft limits. Please understand that these are only suggestions and you don't have to do anything. But if you do it, I'm always happy to hear how it went.
"For any given kink, either nobody does it or more than one person does it." (Ugol's Law)