Unknown T&E Soft game?

Google translation of the YouTube page (always open in a new tab for the infos and eventual comments !) :

In 1989, it is MSX2 + only game made ​​as a memorial of the 35th anniversary planning JC Seto.
Is distributed at the venue of October the same year of "Seto citizen Festival", game competitions were held.

Title: top dog Quest (THE KOMAINU QUEST)
Genre: side-scrolling shooting game
Compatible models: MSX2 + (required MSX-MUSIC)
Media: 3.5 inches 2DD floppy disk

Organized by: Institute of Seto Junior Chamber
Production: T & E SOFT
Supported by: Seto / Seto citizen Festival Committee / Matsushita Electric Industrial Co., Ltd.
(※ company name are things all of the time) city each company: Sponsorship

※ I have captured it after having operated at MSX emulator.
※ I only have us, the software that was distributed at that time, it has nothing to do with JC like Seto.
※ About 10 years ago, I have the written permission of the home page to JC Seto-sama, I had posted a capture image on the home page.

Yes, I already translated it, what is important here is why we know something about this game now. Thank you BTW.

In the vids I didn't notice anything like a "side scrolling shooting game"....

This *is* the game:

http://www.youtube.com/watch?v=bhtV-tu1HjE
http://www.youtube.com/watch?v=LWeJKLC3Chc

Those who prefer to remain spoiler-free: mars2000you's linked video looks to be the end demo...