This is a Castle Wall puzzle, with a twist. None of the clue colors are given initially. For each symmetric pair of clues, exactly one is inside the loop (white) and exactly one is outside the loop (black).
(Click for larger size)
Unrelated to this puzzle: if you’re a Fillomino fan, you will enjoy this puzzle from Anderson Wang, a regular USPC/LMI competitor and someone I’ve met in real life through math contests. His other content is worth doing too, but that one stands out.