No reads. Early in session.

What does villain have?

Party Poker No-Limit Hold'em, $ BB (6 max, 5 handed)

BB ($53.60)
UTG ($45.81)
MP ($50)
Hero ($50.40)
SB ($30.15)

Preflop: Hero is Button with , . MP posts a blind of $0.50. SB posts a blind of $0.25.
UTG calls $0.50, MP (poster) checks, Hero raises to $2, 2 folds, UTG calls $1.50, MP calls $1.50.

Flop: ($6.75) , , (3 players)
UTG calls $43.81 (All-In), MP folds, Hero ???

What else is there to do but fold on this board, that all in could mean a draw but there really are no draws on this board. You only have $2 invested this is an easy fold, as to what your opponant has, I have no idea, this is a stupid bet either way. The only hand that calls him here is a monster, my gut is saying he flopped a set and is hoping to get a call from AK.

At Party, my guess is AQ, A2, or Q2.

If you bluff 7x the pot, that's a move that has to take the pot down almost all the time. Let's see, risking 43.81 to win 6.75: if it's a bluff, in order to be +EV, it would have to get you to fold, um, 86 percent of the time (give or take). Ludicrous as a bluff. So it's almost surely not a bluff. So with your lousy hand you can safely fold and wait for him to make the move again, and next time you'll have a hand you can call with.

I don't really think it matters what he has since you can't call that bet, but I would guess a weak Ace or A2. People tend to slowplay sets.

I'm with Stoneburg. It doesn't really matter what he has as you can't call that bet. Just fold your hand and get on with the next one. If he shows his cards I would be very interested and make a note of what he had and what he did with it. If he went all in with a weak Ace this time he will do it again. Next time when you have the goods and he goes all in you can make him pay.