Comet lucifer is a Mecha/slice of llife/Romance/Fantasy anime. You probably could cram in a few more genre's. At only 12 episodes, this obviously results in problems.
writers essentially said "let's make it up as we go along." That pretty much sums it up. Then they noticed it was almost over and crammed in an ending. And added the final villain because the show kept hinting but never showed one. Who started getting development halfway through the last episode.
Art 8/10 Unique and pretty good.
Sound 7/10 Decent but not very memorable. It was just "there".
Character 4/10 very cliche and forgettable. Mostly consistent though.
watchable. Art was best thing about this.