Go to the alleyway

You decided to hire a prostitute. Though it might be risky, it's a better option rather than finding random people.

Just as you approached behind the alleyway, no one other than a girl with fair light brown skin shows up. Her dyed striped pink hair covered by a black hoodie. Wearing ill' fitting ripped jeans showcasing a matching pink striped thong and some black airforce shoes. Despite covering herself, her enormous cleavage and ass were big enough for you to see forming at her clothes bobbing as she squat and smoke.

You call out that girl, hire her and gave her a general rundown of what you wanna do, you told her you wanna keep something a secret and he'll pay her silence for it. She was hesitant at first, obviously weirded out by the 'being silence' part, but she reluctantly agreed after you paid her half and later on in full.

Now that you have someone, there's some choices you could make

You could, right now shrink down and let her see what you meant by 'secret'. Depending on her reaction it could be good and/or bad at the same time.

Or you could find a better place to do it, like a love motel.