First, I should mention that this is a true sequel to the original Shugo no Tate and that it is based three years after the events at St Terejia Academy. The protagonist, Kisaragi Shuuji (who didn't get together with any of the girls from the original) is stuck in the job of the cross-dressing bodyguard, and he agrees to carry out this one last mission in exchange for the right to stop cross-dressing (lol).
I'm going to say right off the bat that Nozomi is the true/central heroine of this VN. Only in her path are all the aspects of the story fully revealed, and so I advise reading her path last. There are five heroines in this VN... Nozomi (a shy girl who tries not to stand out), Riri (a cross-dressing girl who is immensely popular with the student body), Mana (an air-headed ojousama), Mai (a poison-tongued maid), and Sonya (a Russian transfer student). Like the original, there are a lot of darker aspects hidden under the elegant surface of the school, and those who prefer to avoid serious drama should probably also avoid playing this. Similarly, there are some battle scenes - generally well-described - where the protagonist makes out pretty well.
Shuuji, the protagonist, is an experienced bodyguard and agent, and his combat skills show that. Unfortunately for him, his cross-dressing skills are even greater (lol). I should say that the protagonist is a lot more central to the plot than is customary in most of today's VNs (in other words, he isn't overwhelmed by the impact of the heroines), and the original in this duology was my first experience with the trap protagonist.
Overall, this game is pretty much what you would expect from a game in the same series as the original Shugo no Tate. There is a decent balance between action, drama, romance and slice-of-life without going overwhelmingly in any of the four directions, save at key points. The endings are generally satisfying enough, though people who have played the better AXL games will definitely recognize their style. The original was a kamige, and this was a fun one to play... but it pretty much requires you to have played the original to get the full effect, so it isn't a VN of the Month candidate.
Edit: I should note that some of the heroines have seriously dark pasts, and two of them are about as twisted up inside as the secret heroine from the original. However, like most heroines with twisted pasts, they tend to have some of the best deredere attitudes once they fall in love with the protag.