Well, he regularly gets tricked by the same guys who wear the same obvious disguises sooooo...



I'd imagine Bill would offer Ash the chance to become the greatest Pokémon Trainer in history. And before Ash would object, he would point out all the leagues he lost and that he hasn't made any REAL progress.



So yeah, if Ash can be tricked by the same losers over and over, I can see him being suckered into a deal with the Devil.



Also, why would he monologue about friendship to Bill?