Definitely not for the faint hearted. If you're not a yaoi fan, nor are you into porn then you shouldn't watch this. I myself only bothered with it because I like Yaoi/shounen-ai, and lets face it, there's not that many of those floating around. Plus I wanted to see if this was better then Boku no Pico. However be warned, this is a shota-con where little boys are having sex with older men. Turn back now if you're against that!
Story (3/10) - Shounen Maid Kuro-kun is essentially a porn without plot. What little plot there is only serves to explain how Kuro found himself in this situation serving as a maid in a pervert's house, and that little tidbit at the end where Kuro is given the option to leave. The rest is just porn with a sprinkle of food play, crossdressing, bondage and toys.
Art (7/10) - It wasn't too bad, the animations are kind of weird in some places however (like the twitching dick. I was like WTF?) I didn't like the way Mitsu was drawn, it just didn't... suit. Kuro was cute, I'm glad they didn't make him look /too/ much like a girl as the animators had done in Boku no Pico.
Sound (5/10) - Meh, the moaning gets a little boring after a while.
Character (3/10) - Not much character development, except for Kuro's sense of worthlessness and how Mitsu tells him that this wasn't so. There was a reason why he was chosen. Blah, blah, after that there's not much character development, although they do have quirky personalities. I loved it when Kuro beat Mitsu up :P
Enjoyment (7/10) - It was somewhat enjoyable, for a PWP. The sex scenes were hot at least :) I also found amusement in the beginning when Kuro catches Mitsu spying on him in the change room and bathroom. Go the uke! The last scene was hilarious as well, but you'll just have to watch and see, neh?
Overall (6/10) - Overall I'm giving it a 'fair' rating. I certainly enjoyed Shounen Maid Kuro-kun a lot more then Boku no Pico and any of it's sequels (both animes were made by the same company). It doesn't suit my usual taste in anime, so watching it was just a bit of mindless fun plus smut.
Recommended watching: Boku no Pico, Enzai
-animeangel105
P.S: Fun fact if you did read all of this review - Go check out the person who wrote the script for Shounen Maid Kuro-Kun (who also wrote Boku no Pico) under the staff heading. I couldn't believe my eyes! I mean really? He wrote the script for another of my favourite animes which is immensely popular and definitely not Yaoi/Shounen-Ai o_0