+1 Desu_Cake
+1 Kitten4U
Desu_Cake: If I had to say, simply perfect and perfectly simple
Kitten4U: Same as Desu_Cake. The black and red really bring out an eerie night vibe
EP: It's minimalistic, though not effectively, I think. Otherwise, same advice as usual.
Delfigamer: I always try to spell your name as Delphigamer for some reason. Anyway, it's not bad, but like EP, the minimalistic style choice serves no purpose. Personally, I feel that there should be a reason why one would choose a certain style over another, especially if you choose to forgo detail and decide to use a minimalistic approach. I'd say minimalism generally tries to emphasize certain key qualities of whatever it's trying to portray (or use the minimalistic style to make an artistic point).
Nia: I decided to append myself here because I felt a bit hypocritical after typing the above. Can't say mine is quite minimalistic either.
Others:
Sixten: What I like the best about this is that black guitar jack in cord
Arkeden: Unique, I like it
KazeSenshi: Being that it's just a pencil outline, I can't really say that it's minimalistic or monochromatic (art-wise)
Freeze-Ex: I just realized that this was a gif; I thought my screen brightness was glitching out, haha. This makes me think that Patchoulli has a crystal ball so she can check up on Flan from time to time. I like the messy ink brush-y wings
Merp: I think you're getting better at hair. It looks a lot smoother and like it's flowing. I like the picture in general (and also her bone bat wings).
Vento: I you made mug coasters with this design, I'd totally buy one. It has that noir-ish flavour to it, and the brown makes it quite pleasing to look at. (also, kakkoii, technically)
NotaPirate: It looks pretty cool
Pasu: Same as NotaPirate. I think you're getting better too.
Suikama: Looks cool. But I can't help but feel whether the concept makes sense in the context of her character.
Forgive me, people near the end. I'm starting to get tired of writing this since I started like an hour ago.