Okay, after watching that SumiOni video in detail, I've got to admit that the game is much more Okami than Muramasa unlike i'd first thought.
The paintbrush system is clearly a direct system taken from Okami (except it has a more direct interface with the character this time), though the demon arts are very similar to the system in Muramasa.
Do want 
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CPU - i7 8700K 3.7 GHz (4.7 GHz turbo) 6 cores OC'd to 5.2 GHz with Watercooling (Hydro Series H110i) | MB - Gigabyte Z370 HD3P ATX | Gigabyte GTX 1080ti Gaming OC BLACK 11G (1657 MHz Boost Core / 11010 MHz Memory) | RAM - Corsair DIMM 32GB DDR4, 2400 MHz | PSU - Corsair CX650M (80+ Bronze) 650W | Audio - Asus Essence STX II 7.1 | Monitor - Samsung U28E590D 4K UHD, Freesync, 1 ms, 60 Hz, 28"
