Stratos 4 Recap episode - For everything which happened before Stratos 4 Advance started.

At the academy Miami Takashi attends, higher education has sunk to the lowest levels of depravity, with armed hall monitors, teachers who wear masks to hide their identities and special detention sessions in a torture chamber beneath the gym! It's a curriculum designed to chew up sweet young things, and poor Miami's been voted "Least Likely to Survive" in her class! Is there no hope? Can no one save her? Enter Kekko Kamen, the most outrageous superheroine ever! Clad in a red mask, red boots and nothing else, she is the supreme protector of innocents like Miami. Armed with her trusty nunchaku and a body that just won't quit, she'll make chopped pork out of the swine who run this school from hell! But who is she really? The only one who knows for sure is creator Go Nagai and he's not giving anything away... except lots of free peeks at Kekko Kamen's magnificent physique!

Oraku is a lucky man. He has a comfortable job teaching at a local High School. He has Satsuki, a fellow teacher whom he hopes to marry someday. He has Aya, a beautiful student who has fallen in love with him. He has Aya's father, a wealthy man who wants so much for his little girl to be happy that he has sent her to live with Oraku. Oraku is a very lucky man. Of course Aya loves nothing more than to come on to Oraku by lounging around his apartment half naked. Unfortunately for Oraku, Aya's father happens to be wealthy because he is a major crime boss, and he will have Oraku slowly murdered if Aya doesn't remain absolutely pure. Now Oraku must not only restrain himself, but also protect Aya from the hordes of men and woman at school who'd love to get their hands on her body. And of course, if Satsuki or any of the other teachers find out that Oraku is living with one of his students, he will be permanently dismissed from the teaching profession! Oh yes Oraku is lucky...

Unaired episodes included in the Blu-ray box volumes.