Imagine what if Bi is the true LL. Eiji’s father is the one who covering up for him 15 years ago. Even worse, the old man might not kill himself but Bi did it.
Yeah from the few things we know so far it seems Eiji is the other personality and B1, which might be the real LL or the successor, is actually his real personality.
have multiple personalities must be fucked, since it's like an entirely different person and you don't even realize how long has passed before you are back.