
Is it me or is the whale, Terra, duke Castillo...?

Do you mean the ML's father? That would make sense. But not if you meant the ML. Their personalities are far too different. Plus I can't figure out what reason he would have to continue to pretend to be just the indifferent and arrogant Castillo son, even if the strange woman was his mother and the human duke his father. Finally I think the whale has more to do with tht same strange woman who allowed Lippe's rebirth. Not saying they're the same being though because they have different personalities as well.
Yo~ they could have elaborated the treatment scene more... ( ̄ε(# ̄)Σ