Outlines are A-OK if you're a lazy artist.
I'm a lazy artist.
Don't be Mikau Kahn.
Love this aesthetic, hope you keep posting!
Don't add lines D:
Lines are for noobs. Also they look bad.
Semont is right that it doesn't need a hard outline per se - it's much stronger for being blocked. However, what is the purpose of an outline? To distinguish the piece from its surroundings, correct? W4rlock is right that you need to do something about that. Basically, many of your colors are so light that, when viewed at 100% zoom, certain parts (like the legs) fade into the white background.
You have a couple options. the first is an outline, but I don't think that fits this piece. Second, you can use your other colors to help refine the shapes to define the edges better - this is plausible, but since this piece uses solid blocks without shading, it wouldn't quite fit. Third, and best, you could remove the white background. Doing that does a LOT to help your readability.
I really like this piece for some reason. There are a lot of technical pixel flaws (color near-clones like the face to the skin, jagged curves like the back of the blade, diificulty distinguishing what her left arm is doing, etc) but some combination of the character, the design, and the general aesthetic looks really promising to me. I'm interested to see what you do next, whether it's an enhanced edit of this piece or something new.
Well, not all pixelart needs outline. It really depends on the style but outlining is a much more popular method of drawing.
it is fine but it needs outline.