As bodies droop, jiggle, fold, wrinkle and deflate, Dr. Tony Youn is there. He’s a plastic surgeon—and a busy one, the reconstructor of more than 5,000 parts, from protruding ears to curve-less derrieres. He shares stories from the trenches in his memoir, In Stitches, which begins with his awkward childhood days. Growing up as one of two Asian American kids in his entire midwestern hometown, Youn never felt comfortable in his skin. It didn’t help that he had a bowl-cut hairdo, Coke-bottle glasses, headgear, and what he describes as a “comic-book jaw.” Getting surgery to reconstruct his jaw would change his life. Wanting to help others find the same confidence he did, he became a self-described expert in beauty and aging.

The Michigan-based doctor, who released a new book called The Age Fix, appeared for a Reddit AMA, writing, “In my 16 years as a plastic surgeon, I’ve seen and heard it all.”

Here’s what we learned about Youn’s wild world of plastic surgery.

Among the wildest moments of his career was using leeches to save nipples.

The worms have actually made a modern medical comeback, helping doctors “do everything from reattach severed fingers to treat potentially fatal circulation disorders.”

Clients have requested wings. Actual wings.

There may be an alternative use for liposuctioned fat.

We’re all for clean energy, buuuuuuut no.

He has some guesses on who’s had work done in Hollywood.

Yep, face transplants are already a thing.

In this video, Youn talks about how every blood vessel and nerve must be reattached in a face transplant.

He has strong opinions on plastic surgery for minors.

He may be using his scalpel much less in the coming years.

There are many ways to improve their beauty without going under the knife.

Some people have very unrealistic expectations in desiring plastic surgery.

There are important things to look for when choosing a plastic surgeon.

He gives his thoughts on the comparison to the TV show Nip/Tuck.