Just to give you an idea:
SPOILER
The events in the ultimate harem ending occur after a three-year timeskip. For some reason, all seven women are now sharing the same body type, which means Irene and Rachel now have the voluptuous figure and G-cup breasts as Sen/Theo/Vera. The medieval torture chamber in the house is now dubbed as the "training room" and one of the scenes in there involve Rachel and Elisa both straddling on a 'wooden horse'. Meanwhile, Theo, Uno, and Vera are naked inside a prison cell with their breasts peeking out from the gaps of the jail bars. Irene and Sen, wearing only collars, are on a bed in a corner of the room waiting for their turn.
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My favorites are Sen and Theo. I think both women have the best chemistry with the MC, and their rivalry could've been interesting as an overarching plot with proper writing.