This is an OVA released on October 27th, 2006. It is also classified as the 13th episode (thus a sequel) to Kashimashi ~Girl Meets Girl~.
Hazumu confessed his love to Yasuna, but she turned him down him. To ease his heartbreak, he went to Mt. Kashimayama where he had met her first. However he lost his way in the mountain, and it was night time. He saw a big shooting star, and when he began to wish, he found out that something was wrong. It was not a shooting star, but it was a falling space ship. He was involved in the crash, but he managed to survive by the help of an alien. However, he became a girl due to the accident during the reconstruction of his body.+ More
Characters & Voice Actors

Kamiizumi, Yasuna
Main
Horie, Yui
Japanese
Kurusu, Tomari
Main
Tamura, Yukari
Japanese
Osaragi, Hazumu
Main
Ueda, Kana
Japanese
Kameyama, Natsuko
Supporting
Satou, Rina
Japanese
Mari, Ayuki
Supporting
Asano, Masumi
Japanese
Osaragi, Kahoru
Supporting
Devon, Mari
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