A very promising demo so far! I love the visual style of the game, with its vivid backgrounds and equally-colorful character art, which has an eye-catching style that's both elaborate and detailed and very sleek and clean. I love alchemy-based storylines and the fact that the MC is going to run a shop reminds me of the Atelier series: Will there be an actual mechanic for the shop, like making and selling products? That would definitely be something I'd be interested in, though its absence wouldn't be a deal-breaker as I'm interested in seeing how the storyline unfolds around the MC. I'm also looking forward to meeting more of the cast, as the ones we've met already have distinct personalities that make me want to interact with them more. There's also Celestia's comment about the MC's eyes, which makes me think that it'll lead into a larger plotline, somehow.
Overall, what you have is very impressive and I'm looking forward to seeing how the project develops!