sl mc's dad was that who took girls into modelling competition's "house" with boat. trisha being sl mc's dad's lover isn't farfetched since we don't know where she was before dmd but it isn't likely either due same reasons and most likely identity of dad's lover will remain mystery (unless it's trisha and she spills the beans). melody had her own antagonist so didn't need other and dee lived in big city when she was harassed by lucas and melody lived in small town.
Oh the yatch's captain yeah but it was in ch 3 not ch 4
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As for Trisha, it's not so much of a mystery since she was one of the owners of the hotel. Trish and Ash's parents lived in Sunshine Bay, so chances are she lived there too. Also, if I'm not mistaken, shorkake said she never left here, and we know she doesn't know who her father is. If we take into account the mysterious envelope, well... There are only a few pieces left in this puzzle to have the complete picture... don't you think?
Well Lucas... Ahhh Lucas! The god of assholes. He could have been in the wrecker's place during Melody's concert. and for the small town, Sunshine Bay is also a small town and he's here so I think he would have been perfectly fit in this role. Maybe Dot was worried about scaring off his customers by overdoing it with him.
NOoooo Not again this vilain!!! Not him
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But hey! You know what?
We'll wait and see