Welcome Gabriella,
I think you actually don't need a topic. What I find to be effective is that a model can run away with comments the guys make. Comment on them and expand them into secondary questions, with the hope that more guys will jump into the chat. You're the hostess, but you needn't have cue cards for topics. The guys in your room will say enough that you can reply to and cue in on to elaborate.
If I may, let the guys spend a couple minutes in your room, then include them in the conversation. I'm really less inclined to spend and start great conversations with a girl who says 'I'm so horny amicu bb' the moment I've walked into the room. For one thing, my page is still loading and I may miss the first hello and only get the 'talk to me amicu' response sometime after. For another, after a couple of minutes I have a nice sense of the way a model operates, whether I should say something geared toward sex, which I fumble with, or something clever, which I have more comfort with. And should she give me a little time to gain my balance before asking, "what about you amicu, I saw you come in a little a while ago, no need to be shy, what do you think about ___?".. I am more apt to reply, and much more likely to carry a conversation.
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