He was born to deadbeat parents on the stinking hot plains of Nakhon Sawan, a central province a couple of hours' drive north of Bangkok.
At the age of 10 his parents fled to Bangkok looking for work on building sites, placing him in the care of his maternal grandmother. The parents promised to be back in six months to pick him up; they never did.
Poverty and a lack of anybody to guide the grandmother's buffalo meant that once he'd finished Grade 6 he was out of school and into those fields.
He was in trouble as a teenager and wound up in a juvenile detention centre, but by the time he came out he had decided to pull himself together.
He tried to get an education. He enrolled in night school to get his high school degree, which is where I met him nearly 15 years ago.
He never finished that degree. He had to go into the army for two years and he also found himself a girlfriend who fell pregnant in no time.
''She is such a nag,'' says Lek of his wife, screwing up his face. ''Always going on about having girlfriends behind her back! Nag nag nag!''
It soon transpires that Lek really has no business down here in the Big Mango. He just wants to escape his wife, visit one or two of his girlfriends here and see some friends such as me and his big brother from juvenile detention days who is now a well-known figure in the Bang Phli underworld while fronting as a motorcycle taxi driver.
''If you want to go anywhere within Soi 54 of Kingkaew Road, you just come and see me,'' says Lek with genuine affection and pride. ''My big brother will take you there _ free!''
But the real reason he is here? Well, because he can. Like I said, he's been unusually rich ever since last Saturday.
''There were two parties handing out money this time,'' he said. It was now edging towards midnight and Lek's face was turning beetroot red thanks to two glasses of whiskey.