So the default font for the VN is Varela Round and is the font used in the text boxes for dialogue and the like during the normal portion of the game. As a tip, you can access the accessibility menu (in this VN and any Renpy VN by default) by pressing the A key while inside the story. That way you can switch back and forth easily to see how changes are affecting things.
Ah, okay, there is a bit of a difference, just not quite the difference I was hoping to see, I suppose. Now that I look closer at the font, it kinda reminds me of the 'Asap' font, which also has rounded edges, but distinguishes lowercase 'L' with a short curl at the bottom. It seems Varela Round also lacks a true italic and bold, which Asap has.
Of course, it'd be too much to ask for a font change for this game. You'd have to go through all the dialog boxes and make sure the text doesn't run out of space and start drawing outside the box everywhere in the game, change all the spacing and sizing of things (or at least make sure they work with the new font), and all that crap.. So don't worry, I'm not at all trying to say you should change anything just because I have niche font preferences.
But I will say that Asap is an excellent font that you might want to consider for your next project :3
Though, thinking about it, I'm not sure if Asap has a kerning pair table.. I know it has an OpenType GPOS table that has both kerning pair and kerning classes, but that might not work with RenPy. I did some extra Googling, and it seems RenPy version 8.2+ can, but it might require doing special shenanigans with the code to enable the Harfbuzz shaping engine.
Actually, I just read a bit more, and it looks like the releases with Harfbuzz support aren't released yet. Latest is 7.6 and 8.1, and the Harfbuzz support is being added to 7.7 and 8.2. So, that's something to look forward to, since it'd let you use fonts that have advanced typographical things like ligatures, class-based kerning, and so on.
Looks like Varela Round also includes some of that, as typing in things like 'Muffin' on that Google Fonts page has the 'ffi' turn into an 'ffi' ligature. So that's something to look forward to in games made with future versions of RenPy :D
Edit: Oh yeah, another good rounded font that I somehow forgot about, and would be quite fitting for anything furry-themed, is Eurofurence. Though it's generally considered to not be so great for large blocks of text.