Hey! I've seen you use a brush a few times in your streams that makes 'hollow' lines, what on earth is it? It looks so useful, It's been driving me crazy!

Sorry it took so long to get to this, Anon! 

Basically this all came about because I am LAZY and will find shortcuts for EVERYTHING if I can. Like detail work. 

HOLLOW LINES: For when you wanna look like you put effort into your details without actually putting the effort in:

So the way I get the “hollow” lines in Clip Studio/Manga Studio is with the “border effect” tool! (A similar effect can be used in Photoshop by using “outer glow” if you play with the settings!)

It’ll be found to the far right, just above “Layers” (or at least it is for me!)

That lil circle-sucker right there. 

You can change the thickness of the outline and even the color of it!

For this, my “edge color” is black. You can then just scribble whatever you want, color it however you want, etc etc.

I often use it for super quick detail work. LOTS OF SWIRLS! 

I hope that helps! 

EDIT (for you Photoshop people!): 

Thank you, @badaxefamily!