Shakugan no Shana - Koi no Kougai Gakushuu. YAAAAAAAAYY!!!!!raw, unfortunately
Chronologically takes place after the twins get blown away and the
pool fight. Less on the hotsprings, less on Shana & Sakai, more on
Tanaka, Eita, and Ogata's crush on the former. Wilehmina and Margery
Daw get short screentimes too.
...and Ogata makes the
BIGGEST fanservice splash... though not
quite in the place you'd think

She came prepared for what the rougher
sex does at hotsprings.
Note to self, you can't take Ike anywhere on roadtrips
Oh yeah, looks like the movie's a go for April 2007. DOUBLE YAY!!
Regards