An intertwining of the soul was naturally an astonishing matter, as Leonel and Aina's union had showed them more than one time before. And it was precisely because of his experience in marriage that Leonel came to understand that his connection with Blackstar wasn't so simple, either.
It could be said that the reason he had never noticed before wasn't because he was too neglectful, but rather because Blackstar was far too unruly. A troublemaker in the truest sense.
In their relationship, Blackstar wasn't the beast, but was rather the man. Back then, Leonel didn't even know how to contract beasts, so the reality of their relationship was that Blackstar was the one in the superior position.