A charming visual novel with an interesting lore and well executed characters! Amazing how much depth was achieved in such a short tale. I thought the starting off in black and white, then ending in color made for a wonderful metaphor for The Grim's mental state. Given the limitations, I think the visual novel had a nice flow and good pacing. Even though some parts were kept intentionally vague, I appreciate we get a better sense of the overall picture when we play through it multiple times, choosing different options to get a better idea of the Grim's character and backstory. The visuals were a little on the dark side (specifically towards the end of the story when The Grim's mental state worsened), but I think that just added more to the overall tone of the story, so I consider that a positive. The voice acting was done well for the most part, but personally I think it would've been better to have not given Gregory a voice. I found it a little immersion-breaking compared to the others.
One constructive criticism I had is the terminologies of the lore threw me off. The narrator uses words like mythic, The Grim, and Barghest ... yet never explains the mythology behind the words and just assumes the reader already knows what they are. A suggestion I'd give (now that the jam is over if the developer wanted to expand upon this) would be to consider inserting a glossary of terminologies to help explain the lore to the reader.
My other complaint is a little more personal, but I feel the story's narration could've been executed better, specifically in terms of perspective. Because the mystery was centered around The Grim's true identity, I found it difficult to connect with him on a personal level. Which leads me to wonder what the story might have been like if we were to read it from the Witch's perspective instead. That way we could be on the same page as The Witch in discovering the mystery for ourselves. It's difficult for me to make choices or roleplay from a character's perspective when I don't know the full details of who they are or what they've been through.
While I did enjoy The Grim and The Witch both as characters. I just found it difficult to relate to The Grim, due to information being purposefully withheld for the sake of that mystery.
Despite my criticisms, I still believe this was a well executed story, especially given the limitations of the O2A2 jam. I'm sure it posed quite a daunting challenge, but this still managed to impress me nevertheless.