It's a marker like brush with a triangle tip. It's slightly transparent but you can change the opacity settings to your liking.
It's a pen I made for faster/messier drawings!
You can use it to line and color a drawing.
![](http://assets.clip-studio.com/en-us/description/1868224/img/ad5e735ac9-204f-bb83-e5c4-94c6f0b8af.jpg)
![](http://assets.clip-studio.com/en-us/description/1868224/img/13c60d835f-7643-a987-ca30-5516627cc3.jpg)
It's a marker like brush with a triangle tip. It's slightly transparent but you can change the opacity settings to your liking.