To commit a bank robbery - ESTP
To cover up a murder - INTJ
To break in and vandalize something - ENFP
To hack into a mainframe - INTP
To get back at a wrongdoer - ENTJ
To sell drugs - ESTJ
It all depends on the kind of crime, I guess.
But for a romantic relationship, I agree with AO but his reasonings can equally apply to INTPs, as well. So, my main guess is INTx. I am with an INTP and there is no one better suited for me.