As a teenager I would shoplift every weekend. I got people in school and college to give me their lists of what they wanted then charge them half the retail price for it. I got caught after a few years and DM's reaction was much scarier than the police who arrested me, so I didn't try it again.
I slept with two guys in one night, but not together. I was working abroad (think somewhere like Zante) and I was having sex with one of the holiday makers at a foam party, half way through I told him to get off as he was shit. I then went off with his best mate a couple hours later; he was much better.
I slept with two brothers. Again this was whilst working abroad. The first brother (after a couple of times of sleeping together) became a little besotted with me and kept telling me he wanted to be with me. He wouldn't back off even though I'd told him I wasn't interested, so one night I came up with the idea of going home with his brother, as I knew they were sharing an apartment. The first brother walked in to find me there. I felt bad for it when I saw how hurt he was, but it worked so I didn't feel too bad.
About 2 years ago I was at a staff party and my assistant manager's fiancé had come up for it (she lived in their home town but he lived closer to work) but she had to leave early to get home for work the next morning. I overheard her bitching about me and another colleague for 'thinking we're babes' and 'acting like a pair of sluts' and saying how we better stay away from her fiancé.
We really didn't think we were babes but I think she was feeling threatened as most of the other people there were either men or women 40+.
In my drunken state I thought fuck her and flirted with fiancé when she'd gone home, and I ended up going home with him (that wasn't original plan but I didn't say no when he suggested it). That is my most shameful moment and I left that job a few months later 
I try not to be naughty anymore, although I did not long ago steal a large jug from work as I thought it would be nice as a vase, and I also stole a latte cup as I'd recently dropped and broken mine and making a latte at home wasn't the same in my standard mug. Work have a fair few of the jugs and cups so nobody has noticed 