A slut. A hoe that likes to have her 'slot' stuffed repeatedly. The higher the amount of the slot, the higher the quality of the slot. A penny slot would be the lowest quality slot known to man. Anyone that exchanges any amount of money for slot insertion is a 'slot machine.'
"Noctem, you mattress-back hoe, you are such a slot machine!"
"Let's go down Sunset Blvd and play the slots!"