.50/1 weird flop donkbet

[2handed]

6max, previous hand with villain I called his raise in the SB with A578 and craised him on a 776 flop, he called, then folded to my push on a blank turn.

Next hand I am on button, effective stacks 120. One limp,
he raises pot, I 3bet pot with KKQ9ds, limper calls, he calls.

Flop J 5 3 rainbow: limper checks, villain bets 27 into 49 dollar pot, my action?