Rush the Hina 　

Plot Point: Well, this is easy. There isn't one. Literally. You have to game modes, (Rush & Challenge) and picking one just immediately tosses you straight into the game.

How it Works: Well, you jump. And that's about it. Hina runs automatically at a set speed. There are gaps in the platforms, and it's your job to jump over them to make it to the exit/ as far as possible, depending on which mode you're playing. Also, Hina has double-jump capability. If the double-jump isn't enough for you, after you've used up both of your jumps you can continue to tap the jump button which will make Hina spin/hover up slowly into the air. However, you can't do this forever, as Hina has a stamina gauge which lowers as you spin.

Items that I guess I can mention:

Horseshoe-type orb item: Yeah, I'm not exactly sure what it's supposed to be, but it raises Hina's move speed. It also gives her silly little swirls where her feet should go. Just to mention that.
"Orz" orbs: I think they say "Orz" in the middle. Not sure. However, I do know that they drain a heck ton of your stamina meter, so avoid touching them.
EDIT: Apparently "orz" is some emote for defeat, so yeah. That's a thing. Applauds and stuff to Swfw
Black hole-type orb: Yeah, sorry. I don't have a clue what this does. Someone should be kind enough to mention it, if you find out.
Spirits: You find these all over the place. They're the bottom number in the top right corner of the screen. I guess they're added to your "score" or some such.

Extras

1. Yeah, sorry, but I didn't do a very good job with the items.
2. The number in the very top-right corner is your distance.
3. The Green things next to your Stamina are your lives.