I haven't been there long but him playing like this means people are pushing more marginal stuff against him and he just catching some cards and draws to keep him winning.
This is from memory so some of the details are missing.
Maniac is UTG and raises max to 1.75, I call with KKJxss in spades to King. 5 total players see the flop. Flop is
[3s]
SB bets pot (about full stack, same as me). Maniac calls which means he doesn't have much. I put in max raise for almost my entire stack. Folds to sb who pushes a couple euros more, manaic folds. I call obviously. What do you think before results?
[9s]