Is it permissible to have the sprites appear as silhouettes?

question, lets say theoretically I want to put a face of a sprite over another sprite, is that ok?

I'm making a visual novel with the asset pack (yeah, I know...), and it's proving very restrictive to use either of the two given fonts for dialogue.  Is there any way I can just use a system font (I'm on windows). I'll understand if you say no -- I'm sure there's a way, I just haven't found it yet, and time is short!

Is there by any chance a .ttf font which is the same as the small text in the pack. That would be perfect.