I agree, the central culprit most likely has something against Battler.
My theory: Asumu had a son 18 years ago, who is not the Battler we know. Kanon's real name is not known, and very little is known about his childhood, and he could possibly be 18 years old and just look young for his age. Maybe he's the real 'Battler Ushiromiya', and he's taking revenge on Battler for taking away his title?
I can't seem to find my last post either...
I'll post it again later and try to word it better because it didn't completely make sense last time.