After making a few more Item World trips to power up Mao's sword I finally got Laharl and the crew to join my team! Now I have the Baal bill in the homeroom with 1% success rate, but I also found a few bribe shops during those Item World runs so I'll be able to stock my inventory full of proper bribes. But it's not like I'm in any rush, since apparently even thinking of giving Baal a shot I'd need to do all the optimal item and reincarnating stuff and I haven't done a single reincarnation yet. I guess it's soon going to be a guide time.