You mean what to bet for or do you mean just different bets? If you mean the second then there are infinite amount of things to bet about.
Bet #1
Sit in the foodcourt and make a bet to see how many men/women pass through a specific point at a specific time frame. You say "women will pass more" or ect..
Seriously... I am not even going to do this. If you just want bets.. think of any type of bet. What the weather will be tomorrow without looking at the weather channel. Who can sleep with another woman first. WHo can make the other orgasm first in bed (My personal fav).
Now if you are actually looking for what to bet FOR.. dear god man that may be even worse of a question

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EvOJ