Making the read 3/6 live

Taken from a live 3/6. Table is typically loose passive, a few tight aggs who fold:

You are the LP, question: what do you think the BB has. BB is a tight with moderate aggression. Not a fish, but young, and you have not seen him at this card room before. BB is up slightly since sitting about 90 minutes ago.

MP calls, LP calls, SB folds, BB checks

Flop K[img]/images/graemlins/club.gif[/img] Q[img]/images/graemlins/diamond.gif[/img] 4[img]/images/graemlins/diamond.gif[/img]
BB: bet
MP: call
LP: raise
BB: reraise
MP: fold
LP: call

Turn Q[img]/images/graemlins/club.gif[/img]
BB: check
LP: ??