Where is that in scripture? Most often when I ask people that they say, "The woman at the well." So I quickly recall the story. God sent Jesus there (we know Jesus had a meeting every morning to find out the Father's will) to talk with a woman who was ready to receive salvation. He went to the well, a place that she went to get the basic necessity of life~water. He met her there, and she received Him. After her conversion, then Jesus hung out with her~a lot. A redeemed prostitute.
He never went to the red light district.
The other passage that gets brought up is when the Pharisees accused Jesus of hanging out with sinners when he ate at Matthew's house after Matthew got saved. But again here, Jesus is sharing a meal at the house of a redeemed sinner who wants his friends to hear about salvation. He's not just "hangin' there with some buddies".
If Jesus really "hung out with prostitutes" he would be compromising His own words:
2 Corinthians 6:16-18 (New International Version)
What agreement is there between the temple of God and idols? For we are the temple of the living God. As God has said: "I will live with them and walk among them, and I will be their God, and they will be my people." "Therefore come out from them and be separate, says the Lord. Touch no unclean thing,
and I will receive you." "I will be a Father to you, and you will be my sons and daughters, says the Lord Almighty."
and this comes to mind:...snatch others from the fire and save them; to others show mercy, mixed with fear—hating even the clothing stained by corrupted flesh. (from the book of Jude, verse 23)
Lord, as you send us out like sheep among wolves, help us to stay true to the Truth when we are living life in You! Help us remember that we will give an account for our spoken words, help them to be pure and true. Amen!