I remember playing some flash game based on some anime/VN. It's a momentum based game where the main guy is hit by a girl on a bicycle and he is sent flying. Objective is trying to get as far as possible. You have limited power-ups to hit him again or change his trajectory. When he's about to hit the ground, other characters are in the street and if you hit the males, they have negative affects. If you hit the girls, some hit you again some do other things. Certain conditions let you get a super hit off.
Sounds like Nanaca Crash, i remember that game
http://tvtropes.org/pmwiki/pmwiki.php/VideoGame/NanacaCrash