Manipulative? That would require him to be sneaky, deceptive, or underhanded. R-18 Sou is so upfront about his lust that the girls are more worried about not getting enough of him. When Maria passes out the first time R-18 Sou tries to sleep with her, he outright refuses to have sex with her and fears she'll die if they do have sex. He's less considerate in R-18, but his fundamental personality and wishes to please the girls are still there.