In a surprisingly pleasant way this episode gave us a continuation of Bobby after Bobby. The case of a uber-powerful ghost killing other ghosts to make himself stronger is clever writing to be sure but it was Bobby and recently deceased hunter Annie that sold the episode as believable and him learning the up and mostly downs of being a ghost. Sam and Dean finally learned that Bobby was tied to his old flask and the reversal of the fat guy who supposedly killed the real villain's wife in life and is actually trying to warn people was a particularly effective twist. The creepiest part being Bobby's ability to see all these evil lost ghosts hanging around while Sam and Dean can't see any of them looming. The other ghost's unwillingness to help was understandable. Certain parts bothered me but the pacing was one unusual to most Supernatural episodes and having Bobby stay behind because they've "still got work to do" makes sense since he has to see Dick Roman burn before he can pass on. But how will he pass on since he ducked his Reaper, he should've gone with them. At least they finally answered the question of why he's still around beyond just the how. But now that they know we can finally focus on finding a way to kill the Leviathans and get Dick Roman out of the picture and give Bobby some peace finally.