I made over PS100 selling my used underwear on Craigslist but my boyfriend doesn't know about it.
Why would you do something you have to keep secret from your boyfriend?
I'm not cheating. I just found a man who has enough money to pay me for my underwear.
While it is okay to sell your underwear to others as they are your possession, it isn't appropriate to hide such things from your partner. Your partner may have reservations about being with someone who engages in a form of sex work and it's wrong for him not to know. You should talk with your partner about selling your underwear on Craigslist and ensure that he is comfortable with you doing so.
I like this new character, I'm going to use it more often. Not cheating and boyfriend is happy about my new underwear fetish.
I hope you understand this is a serious situation and you shouldn't do things that will seem like cheating to your partner. I believe it would be wise to talk to him.