Admittedly I'm not fully on board with Darkstalkers - having only seen pieces of footage and screenshots.
Even then, the aspect that struck me first and most is the overwhelming proportion of the design - with the slender, foreboding bird of prey in the lower half put in contrast against a tough, burley figure on top - which you have also managed to keep its anatomy coherent with the harpy legs. Good stuff!
The toning and shading is also nicely done too, with the highlighting on the legs bringing some nice emphasis on the feathery texture. It would of been superb to see some of this on the wings, but you may have intended to get this done quickly.
I love how detailed it is, but the armor on the others clashes to much with the wings i recommend trying to make them lighter. The muscles on the first man are very realistic yet not, i suggest making them thicker. Unless you want the other four to blend in with the darkness or if the muscles identify your style then go ahead and ignore me. Also i think blue would fit better for the highlights on the wings then purple. Plus the beginning of the wing attached to the arms aren't very large then they get bigger but you have them around equal.