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

Kameyama, Natsuko
Supporting
Mari, Ayuki
Supporting
Osaragi, Kahoru
Supporting
Osaragi, Touru
Supporting
Puu, Jan
Supporting
Sora, Hitoshi
Supporting
Soro, Asuta
SupportingRecommended for you
Martian Successor Nadesico
TV
23m
Kiniro Mosaic: Pretty Days
Movie
50m
Magic Knight Rayearth II
TV
24m
Killer Seven
ONA
11m
Minami-ke Betsubara
OVA
25m
Nanbaka: Season 2
ONA
23m
Saint☆Young Men
OVA
20m
Major 2nd (TV)
TV
24m
Waiting in the Summer
TV
23m
City Hunter: The Motion Picture
Special
90m
The Prince of Tennis II: Specials
Special
23m
Dusk Maiden of Amnesia: Ghost Girl
Special
24m
Yozakura Quartet: Tsuki ni Naku
OVA
28m
Say "I Love You".
TV
24m