1) With the singer I can see some sort of blackmail scenario develop, where she has a boyfriend who makes her "do things" but he is taking video footage of her on the sly. You "save her", for a sexy price... things develop from there where it's realized that it's in fact the Chinese triads who are actually the ones behind it all, they try to force her to take part in some pretty heinous anal AV work with a well endowed Zimbabwean, once again you are the one to jump in to save her from getting properly stretched out, you taking a beating for your troubles and have to make some sort of concession like paying them off. It turns out that you were the one paying off some kung-fu B movie actors who owed you a few favours due to helping them out with their careers, they play the part of mobsters allowing you to become her knight in shining armour, with feelings of indebtedness and vague feelings of love towards you she lets you fuck her in a love hotel where you deviously conspire to cum inside her raw.
2) The assassin, you could see her kill someone but ignore what you see, later on she takes you to a ramen bar for a meal to find out what you think you know and to "thank you" for not opening your mouth, after ordering a beer you put some sort of roofie in it and go to the toilet, you come back and find that she's drunk your beer and is passed out, you know that she was going to kill you after this no matter what so you hail a taxi and take her to a love hotel, she regains consciousness tied to a bed with you furiously licking her out, she's in a panic, as you calmly look into her furious eyes and tell her quite matter-of-fact that there's a much better way for her to use her body that'll guarantee your silence and it'll be a whole lot easier.
3) Daughter of a major conglomerate owner. Something something hotel chain, something something wanting to impress daddy by sealing a deal, something something competition for inheritance, everything has a price, you KNOW what I'm getting at. This little whore with business sense will have to be very active and earn it all the HARD way!
4) Princess, this snow white princess runs away from a marriage that she's having second thoughts about, doesn't know the simply Worldly things but through the kindness of your own heart you let her stay at your hotel seemingly completely free of charge. She orders food, drinks, the whole works, then she receives the bill. You ask her how can she pay for it all, the hotel has a certain reputation so it becomes quite obvious how she's expected to pay... even so you make a suggestion which she grudgingly agrees to, she gets bored so you take her out to a nice restaurant (relatively speaking, Olive Garden) and other places, due to not having servants around you offer her some "special service" and help her to wash up in the bath, your hands rub all over her body soaping up her lewd breasts, she's never felt anything like that before, she gets a bit hot from the bath so you carry princess to bed.