I really love this story! Genius new creation of the twins' *G* Though I have to agree it needs more testing ;-) Very well written and really hot! (I'm not normally a 'cesty person, but this really was enticing.)
As for your postscript: *hugs* I think you covered yourself nicely with the warnings. Besides, if Percy was that opposed, I'm sure he would have stormed out and found the twins and made them stop. I think the books show him to be capable of that :-) I also felt you showed the moment of consent very nicely.