Well, that’s a prank gone right.
Explanation: A few months back someone asked @underversesans whether Cross liked eating chocolate with ketchup. The answer was ‘no’; something along the lines of ‘it’s too disgusting even for Cross’. So I immediately did the most reasonable thing ever: got some chocolate and ketchup and tried that mix — and, guess what? It tastes awesome!
Cross Sans and Underverse belong to @jakei95
Ink belongs to @comyet (though the looks and behavior in this comic are based on the Underverse version)