What how did beelzebub get that much stronger? Wolf said if he was still a demon lord he would have one shot him, but by the looks of it yuan's parents defeat wolf pretty easily, so how come the both of wolf (weaker than his "prime") and Yuan (almost as strong as his parents) not even at the very least break his shield? And shouldn't yuan's parents be able to easily beat beelzebub in the past if they could easily beat wolf? Basically it's like this Yuan's parents > Demon lord Wolf > Past Beelzebub =< Yuan's parents. Which doesn't make sense