
Since everyone is stating thier views, I may as well state mine.

Regarding Sousuke's blushing while with tessa:
It can also be read as Suosuke not knowing how to deal with a female ranking officer who is a bit more aggressive with her feelings and not necessarily due to any lovey dovey feelings on his part. Sousuke has the social skills of a rock when it comes to anything beyond a militiary enviornment. He's more comfortable with Kaname, because of how his relationship started (being nothing more than a mission) and Kaname is nowhere as aggressive in the relationship department as Tessa. Also note that he smiles alot more when Kaname's around than with Tessa.
Regading the Anime/Novels/Manga:
They are all the same story, but told different ways. The major themes will always be the same, even though some of the minor themes are different. Key characters that die, will die, for example. Maybe at a different point, or in a different way, but they will die.
I'll leave it at this, since I can go on till the day after forever.
