For the last story it's like "if i can't have him , no one else can". He basically killed his adopted father because he fell in love with him. He knew that there was no way his adopted father would stop collecting women for his hobby and love only him. In the end he grew up to be twisted like his old man and eventually he killed him, that way his fathers love and the family wealth would be his. There's a sequel "kinpeibai kinden honoo no kuchizuke" to give you an idea of how things played out after that. It's pretty twisted...like father, like son~~cc
Yeah it's just like you say. I mean if someone in love he/she will say " I'm yours and you are mine" so no cheating or polygamy.
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