Its really not that deep, its really easy instead.
1. Buy the Thief Book
2. Sell the clothes from The shopkeeper
3. Undress the Guard and sell it
4 F the shopkeeper at the Front Desk and do it as long as you need for the third girl.
Thats the whole game :)
Ps. You Dont need any Lifepotions or weapons to beat the game atm :)