Throw him a surprise birthday party with some pretty chicks!
My friend ever told me one story before, it's about a guy (Mr A) who lost his virginity to a beautiful person!
What happened was, on Mr A's birthday, his friends throw him a fun loving birthday party. A few beautiful chicks were brought to his party, but Mr A was initially pretty shy, he really doesn't know how to deal with those chicks there.
Guess what!? If you want to teach someone evil things, you will have to use some 'dirty' tricks, and alcoholic drinks could be the thing which will help to boost their courages!
The birthday party went well, everyone enjoys the party especially the birthday boy (Mr A). After many rounds of toast & bottom-up, Mr A drank like a drunken cat!
Amongst all the chicks they brought there, he sticked with a beautiful yet sexy one. When the party ends, Mr A slept with this beautiful chick eventually. And Mr A was extremely high, even if you're to ask him for a thousand dollars, he would give it to you without a second thought!
A playful night was over, and the beautiful chick who slept with Mr A went home before Mr A woke up.
Then when Mr A met his friends in the afternoon, everyone asked him if he enjoys the party and a romantic night with the beautiful chick, he told them that he had a memorable birthday and he enjoyed a lots!
At this point of time, let me tell you a secret which Mr A may not known as of the time my friend told me this experience.
I wonder if you notice I DID NOT used the word "Lady" to refer to the beautiful chick who slept with Mr A, but rather I use words like "Person" or "Chick"!? Did you realised it?
The beautiful chick was actually a lady boy, or what we usually refering to Ah Gua. To be precise, she's a transexual (boobs already implanted)!!!
They're wondering if Mr A knows it, or he just tried to hide up!?!
So back to your question, perhaps you may try to bring your friend for a drink, then continue with your "Mission Impossible". But mind you, all the brothels in GL, DO NOT welcome drunk customers! So I guess if you managed to encourage your friend with some drinks, that would be good enough, need not to make him drunk like hell.
Or if you think this is way too much, then better don't treat him drinks but to use another method instead.
Just my 0.0000000002 cent worth of sharing.
Cheers & have fun with care.