しろクロ～白いこころと黒いツルギ～

Akira leaves his town to observe the first and last major meteor shower in this century and gets in an accident. He regains consciousness when he is attacked by some black life form "Zyphos". A girl appears and rescues him. This way Akira makes the first contact with the extraterrestrial life forms and gets involved in the species confrontation.

[From vndbreview]