From the author's README on Thunderstore

All items from this set has the starting name of "Demon" for you to find it easier in-game

Comes with:

Demon Black Leather Jacket with no wings
2 high rolled skinny jeans, one black, the other gray
1 Slim fit rolled ripped jeans in black
1 Black high crew socks for the high rolled skinny jeans

Install Demon Punk Custom Set

You need ReSkate and your own copy of skate. on Steam.

Open ReSkateLauncher.exe and go to MODS.
Search for Demon Punk Custom Set and click install. The launcher also installs anything it depends on.
Press PLAY. In game, the MODS tab of the ReSkate menu (Insert) turns it on and off.

Or install it by hand: download the .zip and drop it on the launcher window, or unzip it into its own folder in Mods\ beside Skate.exe.

Maps show up in the ReSkate menu's level list. To join a server running a custom map, you need the same map installed. If the game won't load after installing, see known issues.

skatemods doesn't host or review this mod. The download comes straight from Thunderstore. Only install mods you trust, because scripts can run code.