"So, this game has a really deep, convoluted plot that you're expanding upon, then?"

The video game's plot is, in a nutshell:
"Blast-off and strike the evil Bydo Empire!"
Other than referencing a few historical events in the Bydo Wars, as well as the general backgrounds on a few ships, that's pretty much it...

"Then why write a story about a game with so little source material? (or novelize a video game at all...)"

'Cause there's so much potential in the R-Type storyline.

It all hit me when I was playing one of the last stages in 'R-Type Final': the player-ship, deep inside the Bydo's home dimension, drifts through a 'soup' of Bydo matter and monsters. In the background, throughout the level, you can barely discern two nebulous figures, male and female, that appear in the distance and fill the screen. Throughout the stage these figures... uh... 'merge' in various positions quite native to the Kama Sutra, if you know what I mean.
This sight was kinda an 'epiphany' for me because it summarized the series so well: the ideology of the 'Bydo', their all-consuming desire to procreate- and adapt- their hideous relationship with mankind, and the fact that they Bydo are, ultimately, no more monsterous than Doctor Frankenstein's creation, only abused by fear and neglect...

I won't say anymore than that. I don't want to show all my cards here...

"Why Typers?"

The word's a slur for 'Raiden' pilots in my story, but there is another reason for the title.
Anyone with a background in the biological sciences might understand when I say that the Bydo Wars are a battle between species with two 'survival types': Humans, who are 'K-Type', and the Bydo, who are 'R-Type'. So, then, the story literally follows the conflict between 'Typers', so to speak.
Also: very late in the story one of the characters (*cough: Justin*) will get the opportunity to pass judgement on both 'Types' of survival and determine which survival strategy should succeed.

"...Ooookay, but you're putting the WHOLE story online, for everyone to see, for free?..."

Every single individual character in 'Typers', as well as about 75% of the concepts within the story, and over 90% of the events in the story, are all original and fresh.
That said, 'Typers' is NOT a wholly-original work: it is derivative of Irem's franchise in several respects. Setting quality issues aside (which I'm aware do exist...) the only way this story could be professionally published by anyone is for Irem (or whoever now owns the rights to the 'R-Type' franchise) to authorize the story as the official novelization (at least as I understand copyright law...). Despite the merit I see in this story, it's doubtful that the game-makers would want themselves officially associated with this storyline. I try not to be pretentious when I write (try...) but 'Typers' is a fairly cerebral work. It IS NOT a cut-and-dry rendition of the world the game-makers forsaw, and it's not light-hearted in the least. Some of the philosophical issues addressed are controversial (and *possibly* not brought-out too well by the author...)

Also, my eventual solution to the Bydo Wars (which I've completely thought-out from day 1) is a bit of a mind-job, and goes against some of the precepts outlined in the cannonical R-Type storyline (especially the part about the 'evil' Bydo Empire......)