This is purely my opinion:
Theme: This was somewhat related to discovery by the simple fact you need to find the little unsleepy imps. But it's only that therefore can't give it more than 3 stars.
Fun: This game wasn't fun at all, first of all because of the broken mechanics and secondly because finding the little demons is a nightmare. There is almost no difference or highlight on what is a demon and whats not. 1 star.
Controls: They are completely broken, the grunt sometimes work and others doesn't. Also when you grunt you keep the running speed still, therefore you become a skater on grunting mode. Also the jump on platform sometimes works and others doesn't. Definetly needs an overall remake or proper testing. 1 star.
Graphics: They are proper but need some rework on colours and the pixel art needs to be less saturated, specially on the horns of the enemies. 3 stars.
Audio: It can be made by the best musicians, mozard itself, but will never be good if it doesn't exist. The game lacks soundtrack and any SFX which isn't the grunt. 1 star.
Originality: The game just took the hide and seek feature and combined it with simple platforming. 1 star.