Make an event of where you want the person to start at. Set the graphic to the top left frame of whatever you want the spriteshee2t to be. On the second event command page there should be a command entitled Move or something of that nature. Click on it. Proceed to click the buttons of where you want the npc to move. Then I'm guessing you'll want him to talk. Hit message and type something like this.

Hooker: I made pancakes.

(you could also boost the parties' HP)

Set the event to be preconditioned to if event bla is on. At the end of the event set bla to off. Then later, if you want the hooker to be in the house, set the precondition to bla is off. And make the message this time, (in a new event with the same graphic) to:

Hooker: I'm sorry, you ate the pancakes, remember?